Supercharging (this time, it's real)

[Guest F14CRAZY]

IT'S REAL! IT LIVES!

Got the memcal from Ryan today. Had to eat dinner, but starts and idles without issues. Time to go for a little spin around the block...

[Guest F14CRAZY]

Took it for a spin...

It needs some help. The engine accelerates fine to 55 mph (could have gone faster) but only if stepped on slightly. The engine will bog and eventually stall if given any more.

In park, it will smoothly rev up fine, but after about 2000 rpm, it begins hesitating and won't let you give it any more.

It starts and idles fine, though a little rough. Probably will get better. It shifts fine, gets to overdrive, locks up, etc all ok.

I'm using my '89 TPS, at .38V with the engine stopped.

I'm downloading the manual again, but I got a code EO26 too.

Ah! Help please!

[Guest F14CRAZY]

I suppose I might have connected something wrong, like a vacuum line or something. I'll have another look, but I'm pretty sure they're all ok.

I did send this to Ryan also. Will see what he says.

[2seater]

Maybe my terminology is confusing, but what I mean is the main air passage through the LN3 MAF has no wires in it, but the secondary passage, about 3/8" diameter, houses the actual sensor, kind of an indirect sensing method. That is what I mean by the bypass theory. If the amount of air flowing through the sensor passage is modified, it will change the frequency response at the same total air flow. From the little investigation I have done, it appears the frequency range used for the L67 is the same as the LN3, but it has to flow more air. Apparently GM did use a larger 255 gm/sec table in only a few years of the initial L67 production and then changed the table back to similar to the LN3, even a little less. They even changed the ECM values assigned to different frequencies on seemingly identical MAF's. It seems very confusing. It looked like the MAF used on F14's s/c engine is the same style as the LN3. I don't think it is the same integrated MAF/throttle body as used on the L27 TPI manifold, at least it didn't look like one. That construction is different, also made by Hitachi. I have not flow tested the one I have yet. Initially I though the throttle bore was larger but I found it is the same as the separate throttle body for the LN3. The sensor itself appears very similar, although the sensor does sit in the center of the MAF passage in a sub passage. If it was a carburetor, the sensor would reside in the booster venturi with the main air flow around it.

[Guest F14CRAZY]

2seater: I need your wisdom to bail me out of this one

[2seater]

Considering the hybrid you created, you are doing pretty well up to now. There is no doubt it will require tuning. Do you have a scan tool to record all sensors? Hard to diagnose without more data. You could pick a few different sensors to watch and toggle between them in diagnostics to maybe get a handle on what the engine is asking for. Severe knock will make the engine lay over from reduced timing or more likely it wants more fuel. Does the TPS operate over the entire range it should? It may not be getting enough PE or power enrichment. While it won't make much difference, set the TPS as high as you can, like .42 for idle if possible. It may also require some run time to get the ECM programming to adjust to the new air flows and such. Watch the O2 reading if possible and see if it goes lean while trying to accelerate, a very low reading. If I remember right, you don't have EGR at this time. If it is disconnected, the E026 may show up (quad driver). You cound just connect the EGR solenoid assembly and tie it out of harms way. The EGR won't work but the ECM should be happier. Keep at it, but be careful about knock and running lean. Look at the simple and obvious stuff too. Make sure the spark plugs are on the correct coil outputs, vacuum leaks of course and check the fuel pressure. I assume you are using the injectors for the S/C engine. Do they all operate correctly? None are stuck or restricted from sitting?

[Guest F14CRAZY]

I don't exactly have a scan tool. Will the ECC's diagnostic mode be sufficient? I can report back my sensor readings, and I haven't done it before but I gues I could use the snapshot to record data at certain times.

Didn't check the TPS well, will do and report back tomorrow. At set idle to 0.42V.

I'll report back with knock and oxygen info too.

Correct. EGR was turned off by Ryan and I've capped it off.

I can borrow a fuel pressure gauge from our neighborhood mechanic.

Didn't find any air leaks, but will check again. My dad and I were busy looking everything else over (coolant hoses, gas lines, etc).

I wish I knew for sure that the new injectors were okay, but I don't. The yard said it was running fine a month ago since I bought it, but that's all. My Explorer did have an injector stuck open once and it ran pretty bad, and would trash spark plugs in that cylinder. Would turning the ignition on and checking the pressure (and how long it took for it to drop down) be a good test?

BTW, first time I tried starting, it cranked fine but wouldn't fire. Found out I had the two fuel rail hoses reversed. I didn't kill the regulator or anything by doing this, did I?

Thanks again 2seater. If I could, I'd fly in you, Greg, Padgett, and Ryan and figure this goofy car out

[padgett]

Scan tool and ECC will report the same things (Reatta is one of few that does). Be aware that the reading will be what the ECC *thinks* is happening and not necessarily what is. If you have different sensors or MAF, the factors may require fudging though I think Greg's initially ran pretty good with 88 parameters.

One thing to look for is constant knock readings since will retard the spark quite a bit.

Since you have no EGR, you will probably get an EGR error. Could just connect one to the harness but I remember something about the EGR is tested by turning it on and looking for an rpm drop. On Greg's we just disabled the EGR error mechanism

[Guest Greg Ross]

Recheck your ignition wires again, Padgett was surprised how well mine idled and revved up on crossed wires. As Hal suggests, go in and look at knock count is doing, and what o2 numbers look like. A snapshot scan can be misleading since some values fluxuate quite dramatically. Try clearing the E026 fault even if it's active/ current. Be interesting to know what the timing retard number is?

I'm wondering if the orientation of the timing interupter rings is the same on both harmonic balancers? relative position of the keyways on the nose of the crank?

Don't get discouraged, you're just getting started!

[Guest F14CRAZY]

Greg: I did get wondering about the harmonic balancer rings, but if you take a look at the photos I took, they appear the same. Was worried for a few minutes...

I didn't remove any spark plug wires, but I will check them again.

Will post back with the numbers later. High school gets in the way of things, but at least my newspaper hour and my time at career center give me a chance to visit the forum

[2seater]

I don't think intially reversing the fuel lines would kill the regulator, it's a pretty simple mechanism, just a spring and diaphragm, but it is certainly a good idea to check fuel pressure, even better if you can watch it while driving. I found a partially plugged fuel filter that only showed up under a good load (high demand). The pressure test after turning the key off may help to tell if an injector is stuck open but not if stuck closed or restricted. It is normal for the pressure to bleed down over a period of time. If it holds reasonable pressure for an hour or so there probably aren't any large faults. As for a scan tool, it only helps you record for a period of time but isn't any more capable than the onboard stuff. If the lack of performance is consistant, you will have plenty of time to watch different sensors while it is acting up. Greg is right that the O2 reading will fluctuate, but you can see if it is consistantly low, like staying below .5 volts. You could also watch the cross counts to see if it is going rich/lean as it should. The BLM and integrator will give you a good idea if it thinks it is rich or lean too. A simple vacuum gauge connected while the engine is at warm idle may help detect a vacuum leak. I usually see 18-19" of vacuum at idle. Just gather as much data as you can to help narrow the search. Crossed plug wires can make a difference and also crossed injector connections, but the injectors firing out of sequence will tend to get better as speed increases. It sure sounds like lack of fuel, mine would nose over pretty hard with the bad filter, but it could be timing as well. Just getting it running and somewhat driveable is a victory of sorts.

[Guest F14CRAZY]

I didn't have much time today because I had to work, but I fired up the car and let it idle for a few minutes with the mass air flow sensor disconnected, then ran it up to about 2k rpm. Did about the same sputtering as it did.

Will report back with those sensor readings tomorrow. Sorry for the wait, but thanks for all the help

[Guest F14CRAZY]

Lots to check, but I will get those readings...

Would you like them at idle, 1000, 1250, 1500, 1750, 2k rpm or something like that?

I noticed that for maybe half a minute on startup, there was a really loud air noise, like a vacuum line gone wrong. Somewhere from the throttle body area. Couldn't find it, but it went away and the car idles okay. Is this a sign of a worn supercharger?

Will be checking the ignition wires and the injector connectors.

[Guest EDBSO]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">I noticed that for maybe half a minute on startup, there was a really loud air noise, like a vacuum line gone wrong. Somewhere from the throttle body area.. </div></div> Nope just induction noise that is louder on a cold start, no problems.

[manikmekanik]

See if you can get your hands on a GM vetronics Tech-1 scantool, w/mass storage cartrige. These can read all the codes, store in mass cart. and even manipulate data in the ECM. Being in the Mo-town area, your school shop may have one.

[Guest F14CRAZY]

I got thinking...would it possible for my to burn my own memcal programs with ryan were to email them to me? I don't know exactly what's involved with programming. I checked into software and a cable to do it with the not yet finished Car-Puter. Built in, on board ECM programming would be nice, if I knew how to do it

[Guest F14CRAZY]

I got some sensor readings...I switched to the L67 TPS after I got these readings, so they might be very slightly different after this. I can list the sensor codes (ED01, etc) if you wish. I gave all readings a few seconds before recording them. Sorry for not reporting them in order...I need to get into the habit of pressing either YES or NO, and doing it consistently . I went for a spin. Again, it accelerates fine under part throttle, but acceleration will give out with any normal amount of throttle (to floored). With this light acceleration, I got it up to 70 mph and could have went faster. It will give out and do the same thing if you go over about 2250 rpm. It runs fine until that point if you slowly increase throttle.

At idle...

TPS: 0.38

injector pulse width: 4.7-4.9

oxygen sensor voltage: 0.12-0.74, with very rapid, random change in between

spark advance: 25-27

spark angle (knock, Ed16): 0

OLDPA3: 265

oxygen sensor cross counts: 0, 5 (not 0 through 5)

fuel integrator: 128

BLM: 135

air flow: 9.5-10.3, rapidly and randomly changing in between

IAC: 97-102

MAT: 7

ignition cycle counter: 1

[Guest F14CRAZY]

At about 1500-1600 rpm...at this point in testing, the oxygen sensor thingy in diagnostics was blinking like it does, and closed loop operation was, um, in operation...

TPS: 0.48

IGN cycles: 0

coolant temp: 82 (my thermostat and fans are set at 180 degrees f).

air flow: 12-12.4, randomly and rapidly changing in between

MAT: 9

IAC: 68

BLM fuel: 140

INT fuel: 123-131, randomly and rapidly changing in between

oxygen sensor cross counts: 14-20, slowly changing in between

OLD PA3: 265

spark angle: 0

[Guest F14CRAZY]

Now, at a little over 2k rpm, where the engine was running bad and surging up and down...

TPS: 0.68

ED06, injector pulse width: 4.1-6.2

ED07, oxygen sensor voltage: .03-.83, rapidly and randomly changing in between

ED08, spark advance: 29

ED16: 0

ED17: old PA3: 178 (not changing)

ED18, oxygen sensor cross counts: 0-4 (slowly changing in between)

ED19, fuel integrator: 155

ED20, BLM: 90-135 (alternating, either at 90 or 135)

ED21, air flow: 17

Gonna send this out to Ryan also

[2seater]

It looks fairly normal except for the integrator and BLM. As the rpm goes up and starts the erratic operation it could be at the top of the range for the amount of fuel it can add? The BLM should gradually increase with the integrator that high. The BLM shouldn't dance around at a fairly constant speed, although you could be at the border between two cells and the erratic engine behaviour is cycling between them, but I wouldn't think they should be that far apart in adjacent cells? I would guess that Ryan adjusted the range of the BLM for the L67 injectors, we did so several times to get mine close to the desired 128. If operating normally and it needs more fuel, the integrator will rise until it gets to a point where it will cause the BLM to move in the same direction and the process will start over. This process should happen over and over until the BLM has risen far enough to allow the integrator to cycle around the 128 number. It certainly looks like a fueling problem, there just isn't enough to allow for much acceleration, but you can sneak up on the speed with very light throttle.

[Guest F14CRAZY]

I just did some reading...I guess the BLM is long term ECM learning to keep from running too rich/lean, and the integrator is the same but "short" term (I googled and found it on a turbo Buick site).

Do you think it's more like a fuel regulator problem or a fuel pump not doing enough problem?

[Guest F14CRAZY]

Would now be a good time to check the fuel rail pressure?

[2seater]

Uh, yes, fuel is critical, especially on a forced induction engine. A fuel pressure test set isn't too expensive, and can be used on other cars too. It is possible to make a substitute with a #4 JIC swivel fitting (for 1/4 hydraulic flare fittings) which will screw right on the fuel rail pressure tap, however, the core must be removed from the pressure tap. An inexpensive gauge, can be connected to the swivel with fuel injection rated hose. It can be made long enough to tape to the mirror or windshield. 100 psi gauges are available inexpensively or even a tire pressure gauge can be substituted, as long as the bourdon tube inside is brass or stainless. You must be very careful and it should be connected or disconnected when the engine is cool, it will dribble fuel. This isn't the best solution, but it will allow for watching the pressure while driving. The best and safest is a remote fuel pressure gauge with an isolator in between the gauge and the engine.

[Guest F14CRAZY]

My neigborhood mechanic has a real fuel pressure gauge, and I'll drive it to him (few houses down, no big deal). He'll probably let me borrow it. And I guess Advance, Autozone, etc offer them for free rental. I'll get on this tomorrow and report back.

[Guest F14CRAZY]

Got an email from Ryan back today...

<span style="font-weight: bold">Philip, got the data and in looking it over, I have a few questions.

I believe you told me you installed an entire 3800 Series 1 SC and intake manifold onto your engine, correct? Did you use the injectors, TB, all sensors, etc from the SC engine?

Did you change out your in-tank fuel pump for a stronger unit better suited for the SC?

At this point we need to get some fuel pressure readings. You will need to hook up a fuel pressure gauge to the engine and tape it to the windshield - or somewhere you can watch it while driving. Then I want you to go for a drive and report to me the fuel pressure readings at various throttle %.

You should have about 45psi fuel pressure key on, engine off for the first 2 seconds. With the engine idling, the fuel pressure should be about 35-38psi. Under boost, the fuel pressure should climb approx 1psi above base (45psi) per 1 psi of boost. For example, if the SC is pushing 10psi of boost, the fuel pressure should be around 55psi and steady. What do you get?

If you haven't replaced your fuel pump, this MIGHT be one of the reasons why you are having issues. The stock Reatta pump is not designed for boosted applications. However, there still could be a problem with the programming so that is why I want you to check out your fuel pressure.

-ryan</span>

It seems my bad link is fuel pressure. I would have worked on it today, but we had some work to do...being a family of plumbers, and I'm the backhoe operator, we were replacing a fresh water line to a house from the street in the city, and Miss-Dig was a bit off regarding a gas line...nothing bad happened, but it was an awful mess.

But anyway, I will get to obtaining a fuel pressure gauge, and will report back with readings.

[Guest Greg Ross]

Philip,

You were not payung attention in Class! Don B. advised you to change out that Fuel Pump way early on.

When I converted mine to S/C I did a bunch of other things including replacing the Fuel Tank (the orig. was looking pretty shabby on top) and the whole fuel line harness. Used a pristine tank of a '90 and used the latter style plastic fuel/ return kit for a Riviera. The little bit of extra length was no problem BTW. I also had fabricated high pressure ( the sexy looking Stainless Steel braded reinforced-the real stuff) Got end fittings from a salvage yard to mate up to the factory Fittings on the Fuel Rail and had them brazed onto proper crimp type hose end fittings to make the crossover. Now back to the Fuel Pump;

The Carter I purchased aftermarket, and its' been in there for several years now without any problems. The torment was getting it into the tank. The way the factory Fuel Pump is installed as I recall it bacically has self sealing couplers. To substitute the Carter I had to use bits of Hose/ Hose Clamps and throw those factory Bits away. I used a Hose Clamp to mount the Pump its'self to the Riser Pipe. Next trick was to persuede it into the tank, GM never intended the oversized pump in this tank so the opening is small. I had to manouver, press, persuede/ force it in the opening. As I was doing this I thought to myself, "I'm doubtful this will be coming back out of this tank!"

I do suspect you're going to find it is a fuel pressure issue and you'll be into this routine. Good luck with it.

[Guest F14CRAZY]

Thank you Greg. I remember Don B. mentioning it, but then 2seater was like 'aw it's fine." But no big deal.

Today or tomorrow I'll have our neighborhood mechanic check the pressure, but I'm agreeing that I'm most likely not getting enough fuel due to the pump.

Can I go ahead and use an SSEi fuel pump? Would I be swapping the entire pump/gauge sensor assembly or just changing the pump on the assembly?

[Guest Greg Ross]

The SSEI Pump would most likely be fine, problem is I think you're going to end up swapping just the pump since the Tank Top Flange on the SSEI tank is apt to be much larger in daimeter, compare them first though. Second issue then would be the depth of the Tank/ swing of the float arm etc, the reatta Tank might not be deep enough or/ and your Gage accuracy would end up being way off.

Hal,

From the good write-up on Fuel System performance, any option for to switch to the S/C Fuel Rail or, at a minimum the S/C Fuel Regulator (I have a spare I think if you're interested) Is it vacuum variation that's altering the pressure regulators' output? Anything that helps with fuel enrichment under boost has to be going the right way!

Philip,

Attached is an-under-the-hood from Betsy Blue. You should be able to at least see how I tidied up the Wiring Harness'. ran the FI up over the blower rather then having to extend all the leads and all three sensors for the Throttle Body are nested together running again over the top.

[Guest F14CRAZY]

Seems I neglected to deal with this...but there's a cable attached to the transmission that used to connect to the throttle linkages. Is this a kickdown cable? And, how should I go about connecting it with the new throttle body? It doesn't have a provision for it, nor does the black metal thing that the throttle linkages attach to.

[Guest F14CRAZY]

And, it seems that transmission operation is not affected without it (from what mediocre driving I've done with it).

[Guest Greg Ross]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> but there's a cable attached to the transmission that used to connect to the throttle linkages. </div></div>

Seems to me I used the bracket off the 3800 NA throttle body, maybe! I definitely have the two cables but I thought the second one went to Cruise Control Servo?

4000 miles from the source is not much help!

[Guest F14CRAZY]

Yes, the L67 throttle linkages use the two cables. One's for the pedal and the other's the cruise control. However, the LN3 uses a 3rd cable that runs to the top of the transmission. It's a pretty short cable. I checked on our regular LN3 cars again and the black plate that's used do use this cable. I just need to figure out how to attached it to the linkages using the old plate. The L67 linkages don't have a provision for this cable.

[Guest F14CRAZY]

Did a fuel pressure test today! This is what Ryan said recently...

<span style="font-weight: bold">With the engine idling, the fuel pressure should be about 35-38psi. Under boost, the fuel pressure should climb approx 1psi above base (45psi) per 1 psi of boost. For example, if the SC is pushing 10psi of boost, the fuel pressure should be around 55psi and steady. What do you get?</span>

At idle, I'm reading 30 PSI. With throttle applied, I get 40. This is obviously lower than what I need to be producing for proper injector operation. Is it possible that my regulator might be bad? However, yes, the fuel pump has been thought to be the weak link in the stock Reatta equipment I'm using, so, if nobody says otherwise, I'll go ahead and pick up a new SSEi pump.

I found that Intense Racing offers a 255 LPH Walbro pump. They're $99 on ebay, and cheaper than what Advance would charge me for an SSEi pump. Should I go with one of those?

Walbro pump on ebay

[Guest EDBSO]

I would start with the fuel filter.

[Guest F14CRAZY]

Fuel filter was replaced about 5k miles ago

[2seater]

I love the look under your hood Greg Mine is much "busier". As for the fuel rail; from the comparison of the N/A vin C, and the S/C fuel rail, the vin C rail is smoother and larger, IMHO it is superior. I have that same fuel rail as on the S/C engine from the TPI manifold I picked up, and the design looks restrictive? I hope to use the TPI lower manifold with a custom upper plenum and adapt the standard N/A fuel rail to it. The other situation regarding fuel delivery is the regulator. I do not know what the factory setting is for the S/C engine, and it is a different design from the vin C. The stock vin C regulator is a Bosch 237, base setting around 43.5 psi. I am using a Bosch 233 from a GN which has a lower base setting, in the upper 30's, and it is modified to allow adjustment above or below the factory setting. I suspect either style of regulator will do the same thing, normally it sees vacuum and reduces fuel pressure and will rise above base spring pressure in relation to boost pressure, in a 1:1 ratio. I do not have a clue where the S/C engine picks up the boost sensing. It would have to be from below the blower or it will not increase the pressure as it should under boost.

[2seater]

The only thing I can say about the fuel pump is I am using a Walbo 242, a 190 liter per hour pump, and it is plenty for your needs. The Walbro 307 (255 lph)has a higher flow but also a higher amp draw, especially if you go for the high pressure 307. I cannot find the website where I found mine but it was around $88. If you use the large pump, upgrade the feed wire to a larger gauge. The only other concern would be the large pump may have enough flow to overpower the size of that small fuel rail causing pressure to run high. Probably not a problem, but I think it is more pump than you need. The 190 liter pump will supply enough fuel for around 50 lb/hr injectors, way larger than what you will be running.

I am curious about the fuel pressure reading? 30 psi at idle is somewhat low, you said when throttle is applied it jumps to 40? Is this when you blip the throttle or is this a steady elevated speed? The simplest is to simply pull the vacuum line from the regulator and plug it. This will be the zero vacuum setting, or the base spring pressure in the regulator. I confess I am not certain how the S/C pressure regulator is made, but if it is similar to the N/A engine, it is a simple diaphragm and spring. Vacuum pulls against the spring and boost pressure adds to it. A 10 psi change in the pressure roughly corresponds to a change of 20" of Hg vacuum. If the engine is generating 20" of vacuum at idle, it is very tight, I usually see about 18" of vacuum at warm idle. With the engine idling, and you pull the vacuum line from the regulator, the pressure should rise approx. 1 psi for every 2" of Hg vacuum. I looked at the small regulator from the TPI manifold, which looks like the same fuel rail as the S/C, and the regulator does appear to be asymetrical, the diameter of the fuel side is larger than the vacuum side, so the ratio may be different? It is the opposite of what I would expect for a rising rate regulator, where it increases fuel pressure at a faster rate than the increase in boost? As for the fuel filter, I agree to change it again even if low miles. It is easier and cheaper than the pump, and will be a good idea if you change the pump in any case.

[Guest F14CRAZY]

I just got paid. I'll buy my own gauge today so we'll be perfectly certain

[padgett]

Keep in mind that the ECM uses the O2 sensor for PID feedback to adjust the mixture. If the fuel pressure is low the mixture will be leaner than expected. It is going to respond with a rich command and show up in the BLM (long term) and/or Fuel Integrator (immediate) readings.

[Guest F14CRAZY]

Padgett: what does that mean, in simpler terms?