Fox W. Posted May 21, 2018 Share Posted May 21, 2018 (edited) Some here may have seen my addition to the thread here: Well, annoying the old adage 'if it ain't broke, don't fix it' holds true sometimes. I went in for a good cleaning and did a lot of stuff on a fine working engine and now it has little things being odd. It's hard to explain most of what I feel as it's kinda random and not very significant, plus it could be my new engine mount that makes it feel a bit more rough.. but mainly the data is what concerns me: The BLM is 100 at idle, 100 at coasting, and between 108 to 112 under load at any speed. The instant fuel is fine, varying swiftly from 123 to 132 The cross count at idle is 0 to 12 ; and under load tends to be around 3 to 9 (The O2 sensor is new.) The disturbing part is the knock count, anywhere from just under 400, to just under 600. I am very meticulous, I went over everything in fine detail and was very careful. Every sensor is connected and giving data. No sensor seemed to get damaged during all this but I replaced the O2 sensor for good measure. Based on the above, what are the first things I could check? Edited May 21, 2018 by Fox W. (see edit history) Link to comment Share on other sites More sharing options...
2seater Posted May 21, 2018 Share Posted May 21, 2018 Changes to the knock count number is normal. Not that it should keep incrementing upwards while driving, but there is a fair amount of "noise" the sensor picks up when starting the car or small amounts under transient conditions when engine load changes suddenly. It is possible the sensation of greater vibration is being picked up by the sensor? Do the numbers keep changing while driving and does it show any knock retard? Link to comment Share on other sites More sharing options...
padgett Posted May 21, 2018 Share Posted May 21, 2018 +1 they do rattle a bit on startup and may see a few when accelerating from a stop as the timing retards from economy to power. Just means it is doing its job. OTOH if you see increments when cruising then it needs to be checked out. May just be some bad gas. Link to comment Share on other sites More sharing options...
Fox W. Posted May 21, 2018 Author Share Posted May 21, 2018 Thanks, so those super high numbers are not a problem? The answer to if it increases while driving is no, I've never seen it increment in real-time. What about the BLM, does that indicate I'm running lean? My other new issue is that it doesn't start on first, sometimes even second try, it feels like a fuel delivery issue and I also notice the pump sounds much lower frequency, almost strained when it primes at accessory/on. I had replaced the fuel filter, I wonder if it's defective. Volume seems fine though, as I can go to 100Mph no problem. Link to comment Share on other sites More sharing options...
DAVES89 Posted May 21, 2018 Share Posted May 21, 2018 Maybe a fuel system/injector cleaning? Link to comment Share on other sites More sharing options...
2seater Posted May 21, 2018 Share Posted May 21, 2018 The Block Learn is doing its job by keeping the Integrator in the correct range, but, it indicates it is reducing fuel to compensate, so it would indicate excess fuel. A larger than stock injector, fuel pressure too high or possibly one or more leaky injectors could cause this. The first place to check is pull the vacuum line from the pressure regulator and check for fuel leaking through the diaphragm. Another oddball place for pulling a combustible fluid is the vacuum modulator at the transaxle but very rare. Check the fuel pressure if you have a gauge. Dave's suggestion is a good one. Link to comment Share on other sites More sharing options...
Fox W. Posted May 22, 2018 Author Share Posted May 22, 2018 Oh ok, it's true that I do believe these Bosch gen3s are a higher rating than the stock injectors are.. (I didn't do these injectors recently, did these in 2012) I just never looked at my BLM before this issue to see what was normal for my setup, oh well. Link to comment Share on other sites More sharing options...
2seater Posted May 22, 2018 Share Posted May 22, 2018 25 minutes ago, Fox W. said: Oh ok, it's true that I do believe these Bosch gen3s are a higher rating than the stock injectors are.. (I didn't do these injectors recently, did these in 2012) I just never looked at my BLM before this issue to see what was normal for my setup, oh well. That would explain the low BLM. The Bosch type 3 are available in 19# rating which would be stock. It sounds like they may be in the 22#-24# range, if everything else is working properly as mentioned before. If they are, it may run a bit rich when in open loop unless the flow rate is adjusted in the EEPROM. Link to comment Share on other sites More sharing options...
Fox W. Posted May 23, 2018 Author Share Posted May 23, 2018 Some more data: Issues are: takes 2 or 3 tries to start, then runs normal. Sometimes after driving, idle is high, 1050rpm in neutral. Tps at idle .44 Mat: 55 Iac: 46 Air flow 6.3 Blm 100 Spk angle is always 0 Deg spark is 23 at idle, 25 under high load, between 43 to 50 when driving normally, and 32 when coasting down. My water temp is 197 when driving and always 200 to 203 at idle. It used to be lower but maybe that's the new thermostat. The engine feels more shakey at idle and shuts off with more of a shake, but I'm not sure still if that's the new crappy engine mount or not. Link to comment Share on other sites More sharing options...
Fox W. Posted May 23, 2018 Author Share Posted May 23, 2018 Also when idling high, if shut it off and turn it back on, idle is normal. Link to comment Share on other sites More sharing options...
Ronnie Posted May 23, 2018 Share Posted May 23, 2018 You have probably said before, what is the fuel pressure when the problems are happening? Also, the next time it is hard to start, push the gas pedal to the floor and hold it there. See if that helps. Doing that will tell the ECM the engine is flooded and it will stop making the mixture richer during startup. Link to comment Share on other sites More sharing options...
Fox W. Posted May 23, 2018 Author Share Posted May 23, 2018 40 minutes ago, Ronnie said: You have probably said before, what is the fuel pressure when the problems are happening? Also, the next time it is hard to start, push the gas pedal to the floor and hold it there. See if that helps. Doing that will tell the ECM the engine is flooded and it will stop making the mixture richer during startup. I need an external gauge for the pressure right? I'll test it. Also, the temp, related or not, is high I think. I just had it randomly decide to go to 210, then 213, after only 4min of idling. The engine surged a little and it didn't go lower until I started moving. I had already burped the system too. I really don't know what's up. I tried spraying around my intake manifold for leaks and the RPM didn't change, so it doesn't seem like I have a leak there. Link to comment Share on other sites More sharing options...
Fox W. Posted May 23, 2018 Author Share Posted May 23, 2018 Tested fuel pressure at rail, getting 36psi, idle. I didn't test under load. I reved it up in neutral and it raised it slightly. Before turning the engine over, the pressure from the pump-prime goes to about 9psi and then quickly falls off. Link to comment Share on other sites More sharing options...
Fox W. Posted May 23, 2018 Author Share Posted May 23, 2018 Also my idle problem is exactly this: (Never was resolved though) Link to comment Share on other sites More sharing options...
harry yarnell Posted May 23, 2018 Share Posted May 23, 2018 Your pump prime and quick bleed off are NOT normal. Internal leak in regulator, leaking injector, or tank pump would be where I'd look. 1 Link to comment Share on other sites More sharing options...
Ronnie Posted May 23, 2018 Share Posted May 23, 2018 6 hours ago, Fox W. said: Before turning the engine over, the pressure from the pump-prime goes to about 9psi and then quickly falls off. I think you have found the problem that is keeping the engine from starting right up as it should. I just tested the pressure on my car to confirm. After sitting over night the gauge showed 0 psi. I turned the key to the run position without starting the engine. I turned the key off after the pump whet through the prime cycle. The pressure jumped to 41 psi and held steady. After 10 minutes the pressure was still at 34 psi . The last time I remember someone having a quick pressure drop after the prime cycle the problem was a bad connection between the Pulsator and the fuel pump allowing pressure to quickly escape back into the tank. If you do a search you can probably find a long thread about it. If that is the problem you can replace the Pulsator with a rubber hose if you choose to do so The problem could be a bad fuel pump or regulator as well. You should run all the pressure tests on ROJ and see what results you get. Fuel Pressure Testing Link to comment Share on other sites More sharing options...
Ronnie Posted May 23, 2018 Share Posted May 23, 2018 We posted at the same time Harry. Sounds like we are thinking along the same lines. Link to comment Share on other sites More sharing options...
DS_Porter 89 Burgandy Posted May 23, 2018 Share Posted May 23, 2018 I agree. When I turn the key on with a pressure gauge installed the pressure jumps up to 45 psi and holds without dropping if the engine is not cranked. If the engine is started it drops to about 36 psi running. Link to comment Share on other sites More sharing options...
Fox W. Posted May 23, 2018 Author Share Posted May 23, 2018 Alright, I'll focus on my fuel issue then. However it would seem logical for me to focus on 'what changed' last, rather than something totally new. This happened right after I did all that work, which never included anything in the tank. So I need to at first keep my focus under the hood, and no further than the fuel filter (which I replaced) ; the filter isn't leaking. I will check injector seals to the rail. Thanks! Link to comment Share on other sites More sharing options...
harry yarnell Posted May 23, 2018 Share Posted May 23, 2018 Injector seals have nothing to do with this. Link to comment Share on other sites More sharing options...
Fox W. Posted May 23, 2018 Author Share Posted May 23, 2018 (edited) Well what are your thoughts then? If you see the changes that were made, they never involved the tank or pump. My injectors themselves are the same and are very new. Edited May 23, 2018 by Fox W. (see edit history) Link to comment Share on other sites More sharing options...
Fox W. Posted May 23, 2018 Author Share Posted May 23, 2018 My Chinese gauge fell apart, so I can't trust that anyway, need to get a quality one. Link to comment Share on other sites More sharing options...
Ronnie Posted May 23, 2018 Share Posted May 23, 2018 I bought one of these to replace my old Harbor Freight tester. Easy to read and the pressure relief valve on the side is a nice feature. I don't see information on Amazon about where it's made. It's probably Chinese. Hard to avoid anything being Chinese now days. Link to comment Share on other sites More sharing options...
Fox W. Posted May 23, 2018 Author Share Posted May 23, 2018 I didn't see your post before I picked up a Kent-Moore one. Cost me a lot, but I could always sell it after. Link to comment Share on other sites More sharing options...
Fox W. Posted May 31, 2018 Author Share Posted May 31, 2018 I looked around on here and I didn't see anything clear, but is there any new replacement sending units/assemblies available for the 89 Reatta? I think the original part was 25094830 Link to comment Share on other sites More sharing options...
Fox W. Posted June 2, 2018 Author Share Posted June 2, 2018 It's quite a nice gauge. In any case, it holds about 40psi with the pump-prime connected, and about 37psi with the engine running, but all the pressure quickly drains right out to the tank (I believe) when the pump is off. The pressure increases a few psi with the regulators vacuum line disconnected, so I believe the FPR is working fine. It still feels hard to believe this was just a coincidence after I did all that work, but I suppose it may just be.. especially since the hard starting issue didn't happen the first few times I used it after.. but it did happen after I replaced the fuel filter. (which is not leaking.) So I guess next I need to drop the fuel tank. I wish it were possible to get a whole new assembly because I figure I'll have some rust on the lines. test.mp4 Link to comment Share on other sites More sharing options...
padgett Posted June 2, 2018 Share Posted June 2, 2018 Was there any gas in the regulator vacuum line ? Your pressures sound low and the quick drop off says there is a leak somewhere. If hard starting and stumbles a bit that could indicate a leaky injector. Another reader suggested a sender assembly from eBay. Link to comment Share on other sites More sharing options...
DAVES89 Posted June 2, 2018 Share Posted June 2, 2018 I got the same email and I don't know if that one would work as I never had to deal with a fuel pump/sender issue. Maybe Barney could chime in and let us know... Link to comment Share on other sites More sharing options...
Fox W. Posted June 2, 2018 Author Share Posted June 2, 2018 No gas was in the vacuum line for the regulator. If it's a leaky injector, where would it leak from? The bottom in to the plenum? These injectors were totally perfect before removal, and were removed all together (I never removed them from the fuel rail) gently. They are new as of 2012, so that would be another new coincidence. I thought we established a bad pulsator dampener or a fuel-pump check valve was most likely based on my symptoms? It does hard start, but that's because there is no prime-pressure, I wouldn't say it really stumbles at all, just starts as if there isn't enough fuel for the first 3 seconds of cranking and then starts suddenly and normally. I will try to keep the fuel rail connected to the lines at the same time as all 6 injectors are out of the plenum, and I can then run the pump and inspect for leaks. Link to comment Share on other sites More sharing options...
Fox W. Posted June 2, 2018 Author Share Posted June 2, 2018 Does anyone know for sure that this assembly fits our 88-89 cars? I haven't seen any cross-reference that shows this. https://www.ebay.com/itm/Fuel-Tank-Sending-Unit-for-Olds-Delta-88-Pontiac-Buick/110724397764?epid=569757228&hash=item19c7b03ac4:g:u~oAAOSww5hZN7Vp Link to comment Share on other sites More sharing options...
Fox W. Posted September 12, 2018 Author Share Posted September 12, 2018 (edited) I was away on a trip for the whole Summer, back now. Upon returning I have so far pulled the rail/injectors while still all connected up and run the pump to find none of the injectors leak at all. I then dropped the tank, replaced the dampener thing along with the fuel pump, connected it all back up, same thing. So now I'm really needing help.. The only thing I had done related to fuel before this started was replace the filter. The regulator is now the only original thing, but it passed the tests (changes pressure based on vacuum, and no fuel leaks out of the vacuum line, even when the pump is running) Do our fuel filters have a check valve?? I'm really confused what's next. My old pump seemed to properly be only 1-way when I tested it, so its own check valve seemed fine. Edited September 12, 2018 by Fox W. (see edit history) Link to comment Share on other sites More sharing options...
Ronnie Posted September 12, 2018 Share Posted September 12, 2018 Using the proper fittings, I would connect the gauge directly to the pressure line coming from the pump eliminating the regulator and fuel rail as the source of the problem. IF the pump pressure still drains down quickly - fuel leaking at the rubber seal/connector between the Pulsator and the pump is likely the problem. Link to comment Share on other sites More sharing options...
AZVET Posted September 12, 2018 Share Posted September 12, 2018 I have a slightly used fuel pressure regulator for my 88 that I will send you for postage only. I replaced it as I had a leak at the connection to the return fuel line. I then found out that I had chewed up the threads on the fuel line. The regulator came from NAPA. PM me with your address and I will send it to you. 1 Link to comment Share on other sites More sharing options...
Fox W. Posted September 12, 2018 Author Share Posted September 12, 2018 No worries, I already picked up a new one last night for $18, it should arrive in a couple days. I guess the only other thing to do is submerge the pickup assembly fully in water and do 20psi in to the outlet and look for bubbles, as per the shop manual. Link to comment Share on other sites More sharing options...
Fox W. Posted September 13, 2018 Author Share Posted September 13, 2018 (edited) I disconnected the return line from the regulator and put a cup under the regulator output and ran the pump. Fuel shot out instantly and when I stopped the pump it kept draining out. Is this abnormal? I would think that it would not let the fuel drain out unless it was ~>40psi. Edited September 13, 2018 by Fox W. (see edit history) Link to comment Share on other sites More sharing options...
2seater Posted September 13, 2018 Share Posted September 13, 2018 I haven't tested a regulator in that way with fuel but I have applied air pressure and it did not leak air until near the set point in the low 40#'s. It will be interesting to see if replacing the regulator helps. I am experiencing similar issues, nothing from the injectors, no fuel in vacuum line, replaced regulator and problem persists. I don't really want to drop the tank but looking like it. Oh yeah, fuel pressure is normal and responds normally to vacuum, but extended cranking at irregular intervals. Link to comment Share on other sites More sharing options...
Fox W. Posted September 16, 2018 Author Share Posted September 16, 2018 (edited) The regulator seems to have two functions really. Without it, the return flow is wide open.. So its function isn't just to vary the pressure based on its vacuum with the diaphragm, it also is supposed to prevent fuel flow back entirely when it's below 40psi. The thing is, the new one I put on did mostly fix the problem. But it's still not quite in spec I don't think.. though it is good enough. I hear it open at 40psi, but then it fairly quickly tends to still bleed down to 30psi, and from there very slowly bleeds down to 5psi, but still much faster than I hear some people say.. Some say their rail holds 40psi for a day or more. *shrug* I -thoroughly- tested the input line (output from pump) and it is not flowing back with that path, not even slightly. I submerged my assembly in water, and blew 20psi in to the out, and zero bubbles or pressure loss. I also put a block-off bolt in to the regulators' output for the return line, just entirely block that off, I ran the pump for half a second to charge the rail to 40psi and there was zero loss. Therefore all my loss is through the return, through the regulator. In any case the car starts, runs and drives great now, so I'm happy. BUT, my damn fuel sending unit doesn't work right now, it reads I have an 1/8th when I have a full tank. gerrrrr. Maybe from the water test, I don't know, but it's unhappy now. I dread dropping the tank all over again, what a pain in the #*@. My unit has two short lines, and the vapor is a long steel line. On the other side there are rubber lines that mate to these. Delphi HP10010 seems to be the closest new replacement match I can find. It's vapor line is short but you can just use rubber for that anyway. Anyone know if that unit will fit right with our lines? Edited September 16, 2018 by Fox W. (see edit history) Link to comment Share on other sites More sharing options...
Fox W. Posted November 28, 2018 Author Share Posted November 28, 2018 Anyone have a sending unit for sale that fits an 89 with the shorter lines? Link to comment Share on other sites More sharing options...
Barney Eaton Posted November 28, 2018 Share Posted November 28, 2018 I think you will find that repairing your existing sending unit is easier (and cheaper) than trying to find a good used unit. GM used the same sending unit parts on most of their cars back then, so by finding a decent unit, you can move it to your assembly. Usually one of the two parts shown below has failed. The first part is the wiper......the long part rubs against the wire wrapped on the strip shown in the second picture. The wiper is pretty fragile and the wiper may not be touching the wire wrap or it is broken and I have seen the two small wipers broken. The wire wrap sometimes has an "open" and that will cause the gage not to function ..... Link to comment Share on other sites More sharing options...
Fox W. Posted December 27, 2018 Author Share Posted December 27, 2018 Thanks Barney. I'm just trying to see if anyone can confirm if Delphi HP10010 will fit Reatta's that use the short lines? Link to comment Share on other sites More sharing options...
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