starts, then stalls

[Ronnie]

... Given the history of electrical malfunction you've had with this car now (BCM/EEPROM failure) I'm starting to wonder if your ECM got smoked also. That said, being a 90 I presume it still has Magnavox iginition on it. These ignition modules are failure prone - more so than the Delco setup used in 91 - so it may be suspect also. Typical failure mode is leaking of the green slime which causes the module to overheat and self destruct the electonics

New replacements for both versions and their associated coil packs are still readily available and if you are near a you-pick yard they are plentiful on many GM's equipped with the 380p from 88-90 (for the Magnavox type). Whether they are any good is the issue, if you can get one cheap with an exchange warranty then buy a used one to try.

This is all just a suggestion. If you happen to have a spare ECM you might try swapping it in to see what you get. Unfortunately, the diagnostics on these cars misses a lot of powertrain faults and then fails to set any useful codes leaving us to do seat of the pants troubleshooting...

 

Stanley,

 

I agree with Kevin. It is probably time to start swapping parts until you find the one that is causing the problem. I was trying to lead you down a path that would - through a process of elimination - keep narrowing down the list of components that could cause the engine to stall until you found the problem. Although that isn't the fastest or easiest way to troubleshoot a problem like yours it is the cheapest because randomly swapping parts can get expensive. However, after you described what is going on when you try to keep the engine running at 2000 RPM, there is no clear path to follow from here.

 

If it were me I would start with swapping out the Crankshaft Position Sensor because it is a cheap part that (in my mind) might be the most likely to cause the erratic fluctuation in the tachometer reading but swapping out the crankshaft sensor isn't any more logical than Kevin's suggestion to swap out the ECM and it will take more time to change out the crankshaft sensor.

Edited October 2, 2015 by Ronnie (see edit history)

[padgett]

a) I have seen ICMs fail in almost any way possible.

Secondary ignition issues (ICM, coils, plug wires, plugs can do almost anything but do not set codes.

c) Just for S&G, disconnect the alternator and just run on battery for a while. Enough noise coming from the alternator could make the tach (and ECM) go wonkey

d) You don't have a battery charger conected do you ?

e) E026 is the quad driver and should not kill an engine.

[Blue90]

Kevin, Ronnie, Padgett, et al,

SUCCESS!  I pulled the wiring harnesses from my ECM and attached them to a spare, but untested, ECM I had aquired from a U-Pull.  I started up the engine, it fired up right away, RPM went to 1100.  Engine ran smooth for a few minutes, RPM went to ~ 800, I put it into gear and went fo a drive for the first time in over 4 months!

After about 10 miles of driving around the neighborhood, stopping occasionally, shutting engine off, starting and driving again, car ran flawlessly.  Every time I shut it off I checked for codes.  Sometimes e026h and b440h showed, but car continued to run smoothly.

I am now in the process of putting everything back together.  I won't mention on a public forum what I think of the engineer who designed the access for the ECM, but would it still be fun if it was easy?

A very grateful thank you to everyone who gave advice and encouragement along the way.  I truly appreciate the help I received from people whom I have never met yet we have bonded through a shared appreciation of an automobile. 

Many of us come from different everthings ( age, race, geographic distribution, politics, etc.) but this incredible vehicle, the Buick Reatta, makes us all best friends.

Thank you again,

Stanley

[Blue90]

Padgett,

I didn't see your post before I posted my response.

When the car was just sitting idle for a long time I did connect a solar batter maintainer.  I don't remember the voltage it collected but it was quite low.

Thanks, S.

[Blue90]

So basically, amidst all the testing, I replaced the BCM with a good used unit, had a spare 1990 Reatta eeprom reprogrammed for my specific vehicle and replaced the ECM with a good used unit.

I still don't know what made the BCM to abandon all reason but right now life is good.

S.

[padgett]

Glad you found it and makes sense just rarely fails that way. Why it is good to have spare modules, somethines when intelligence fails, swapping is what is left. Did the EO26 clear also ?

[Blue90]

I went for another drive this morning and the e026h code returned.

The code sets while I am driving or idling; comes on as soon as I turned the key on, even after being cleared.

S.

[padgett]

OK. That is the Quad Driver. The diagnostice will let you exercise the fans and other devices. Should be able to hear if they work. What ever does not work is what needs checking out but can be reasonably sure it is not the ECM.

[Blue90]

I located the e026 code info in the FSM on pp 8D1-34 to 8D1-39.

I'll try to get into diagnostics tomorrow and trace it down.

Thanks,

S.

[Blue90]

I got into diagnostics today for ECM Output.  It appears as if EO07, canister purge solenoid, is my demon.

I found references to this in past posts on this Forum but nothing actually in how to remove the canister and check the solenoid.

Should I start a new thread since the car is no longer stalling?

Thanks,

S.

[2seater]

The solenoid is removable from the top of the canister without removing the canister itself. The assembly is located below the engine air filter housing and would be easiest to access after removing the air box assembly.

[Blue90]

Thank you 2seater.  I was a bit confused until I realized I had to remove the whole air box assembly.

I found the shiny, hard plastic line to the top of the canister disconnected.  I figured great, this is why I'm getting the EO26 code. I connected the tubing back up but still got the same code.

So I removed the vapor canister purge solenoid (sometimes called the switch): went to my FLAPS with solenoid and #s in hand. 

They checked and cross-referenced #s of different manufacturers and distributors.

Bottom line - unobtanium, as Padgett would say.

RockAuto says part is out of stock, as does every other site I tried.

I could find one in a pick-n-pull.  Is it worth putting in a used, untested solenoid?

Any ideas would be greatly appreciated.

Thanks, S.

[Blue90]

BTW, vapor canister purge solenoid part #s: Standard Motor Products CP 216.

Borg Warner (OEM) 214570, 25530972.

[Guest HuevosRanchero]

does it look like this??

 

CP 216 came up as a cross reference.

 

http://www.ebay.com/itm/Vapor-Canister-Shutoff-Valve-Dorman-911-762-/311186655780?hash=item48742b8a24&vxp=mtr

[Ronnie]

That's not the one. I believe this is it.

 

Edited October 7, 2015 by Ronnie (see edit history)

[Guest HuevosRanchero]

That's not the one. I believe this is it.

 

 

 

if thats the one jump on this

 

http://www.ebay.com/itm/New-ACDelco-GM-OEM-25530972-Vapor-Canister-Purge-Solenoid-214-570-NOS-14-C1-3-/141704665865?fits=Model%3AReatta&hash=item20fe419b09&vxp=mtr

 

appears to be correct from the picture.

[Blue90]

Thank you Ronnie and HuevosRanchero.

I just ordered it from ebay.

S.

[Ronnie]

if thats the one jump on this

 

http://www.ebay.com/itm/New-ACDelco-GM-OEM-25530972-Vapor-Canister-Purge-Solenoid-214-570-NOS-14-C1-3-/141704665865?fits=Model%3AReatta&hash=item20fe419b09&vxp=mtr

 

appears to be correct from the picture.

 

Good work! GM 25530972 is the correct part number.

[ChrisWhewell]

Sorry if I'm naive' , but is there a system on the Reatta that cuts off the fuel pump in case an accident is sensed ?   Or cuts off the motor if oil pressure drops to a particular low level ?    If such a system is present, it could be worth looking into.   Sorry I didn't read all the posts, if this has already been covered I apologize for the redundancy

[Blue90]

I believe that if the oil pressure regulator senses low oil pressure it sends a signal to shut off the fuel pump.

However, in my case I have proven through testing that it is not a fuel delivery problem.

The vapor canister purge solenoid I ordered is supposed to be delivered today.

After I install it I'll report back; hopefully good news.

S.

[Blue90]

Vapor canister purge solenoid arrived today.  I installed it and put everything back together.

Engine started right up, ran smoothly, but when I checked diagnostics the EO26 code returned.  I erased it.

I disconnected the negative, then the negative and positive battery cables.  Hooked the cables back up, erased the expected B code and started the engine,  No more codes!

This is only at idle sitting in my carport as it's pouring out today (can't complain, we need the water).

Tomorrow I'll take it for a test drive.

S.

[Blue90]

I went on a few rides today, one with Karen-not-a-mechanic, and the car handled great. The engine had one little miss when I was driving slow in the city, but otherwise engine ran smooth, idled well.

However, the EO26h code is fairly constant.  I clear the code and it returns immediately.

Unless anyone has any other suggestions I will keep working on this but as the car is running so well I think I'll live with the code.

S.

[padgett]

Just to go through the diagnostics and exercise the other outputs (can turn on with overrides). Something should not work as expected.

[Blue90]

I'm hoping to go through the diagnostics tomorrow to check the other outputs.

We're leaving Wednesday for a couple of weeks in central California. 

Unless I find something tomorrow it'll have to wait for awhile.

Thank you Padgett for keeping me on track.

S.

[KDirk]

Sounds more and more like this ECM is also faulty. The QDM (quad driver) is an IC within the ECM. The E026 code is triggered when one or more of the four driver outputs of the chip do not respond as commanded by the CPU in the ECM. If the quad driver is not responding to CPU commanded operation then it has likely been damaged by either an external failure of a QDM controlled device or by an internal malfunction within the ECM (i.e. voltage spike or similar event). The CPU monitors the outputs of the QDM versus the commanded input (off or on for each of the four ports). If the actual state of each port doesn't match what the CPU has requested then code E026 is set. Keep in mind that the QDM is simply a switch closure which in turn controls the ground to a relay coil which in turn determines if the attached load is on or off. Power to the loaf is controlled by the relay contacts, the position of the contacts are controlled by the relay coil. Power to the relay coil is determined by it's respective QDM port being "on".

When I purchased my scrub 88 neither the A/C compressor or the cooling fans would operate. They could be run manually by jumping the respective circuits at the relay center but due to two damaged QDM outputs, the ECM could not control them normally. I replaced the ECM and solved both problems. I would warn that rebuilt ECM's seem to be a real crap shoot. I went through three before I got one that worked 100% correctly. Might almost be better off trying used ones from a u-pick yard if you can get an exchange warranty on them. Certainly cheaper than buying a rebuilt.

I presume the ECM you are running presently is a used pull? Do you know the history or disposition of the donor car? Sounds to me like it was damaged previously and you are now seeing the results of that. QDM failures seem to be one of the more common problems with the ECM used on these cars, as though they are a weak link on the hardware.

KDirk

[Blue90]

I went through diagnostics today checking ECM and BCM data, outputs, inputs, overrides; everything was within the parameters outlined for each code.

I did pull the ECM and replaced it with an untested unit gathered at a pick-n-pull.  I went for a ride and for the first 10 minutes all went well; I checked diagnostics as I was driving and no E or B codes appeared.  Just as I was pulling into the driveway I checked again and there it was, EO26h.

When I replaced the last ECM, also an untested u-pick, I heard a hissing sound from behind the glove box.  I attributed it to something with the HVAC for when I pulled the BCM I noticed the little plastic thingy that connected the heat/cold door has disintegrated and I had hooked up a quick fix.

After I hooked up the next ECM I realized the hissing was coming from the ECM itself, probably not a good sign.

While I'm in California I'll try to find a u-pick and get another ECM.  All of the ECMs I've used have come from 1990 Reattas.  Does the ECM have to be from a '90?

Thanks,

S.

[Ronnie]

Have you went through this troubleshooting guide for code E026? Code E026 Troubleshooting

[KDirk]

89 and 90 share an identical ECM. MEM-CALs are different between model years and cannot be interchanged. If you haven't already done the diagnostics Ronnie referenced, do that before writing off the current ECM. I'd recommend getting a spare or two if you can find them cheap enough anyway, as a bad ECM will often leave the car undriveable (as has already happened to you) and so it is a critical part to have on hand to minimize downtime.

I know I am a bit obsessive about having spare parts, but I rather like the feeling of going to the basement and pulling a spare module to replace one that just died instead of making a special run and dropping $150 at the auto parts store. Planning and preparation have saved me money and inconvenience multiple times in my ownership of Reattae. I also wonder how much longer rebuilt modules for cars of this era will be readily available.

KDirk

[Blue90]

OK, here is the latest update from EO26 central in PDX.  

I returned from sunny and warm California w/o finding an ECM.  I bought a used, tested one from Mr Jim Finn.

I attached all the electrical connections, went through all the trouble shooting regimes and still showed the EO26 code.

I put everything back together; the BCM in its mount (I found the little plastic thingy that helps control the heat/cold door had disintegrated. I had been having trouble controlling the temperature for a while, I knew the problem, I just waited for an opportunity to rip it all apart.  I found the part in an '89 Riviera.  Through either prayer or swearing, I'm not sure which, I managed to remove this 26-year old plastic piece whole, from the Riviera to my Reatta) , the ECM jammed into its place, replacing the dashboard, the glove box and the passenger side under dash cover.

For the first time in almost 6 months I'm enjoying driving my car again.

It looks good w/o any wires or metal boxes hanging from under the dash.  And it drives wonderfully.

I'm comitted to working on and solving this EO26 code, but at this point the car is running beautifully and all I've tried has checked out.

S.

[Machiner 55]

Stanley,

 

Does your "SES"  (Check Engine) light come on when you press the "TEST" button on the IPC?

 

John F.

[DAVES89]

That little plastic thingy is also found in the doors. I come across cars that already have door panels off and the part is exposed waiting to be removed.

[Blue90]

Stanley,

 

Does your "SES"  (Check Engine) light come on when you press the "TEST" button on the IPC?

 

John F.

Good to hear from you again, John. 

I just went out and checked and the SES light does not

come on when I press the TEST button.

S.

[Machiner 55]

Stan,

 

I should have checked this this morning. Apparently the SES light does NOT illuminate when pressing the TEST button.

My next question is, does the SES lamp illuminate when the ignition key is turned to the "ON" position?

The reason I ask is, if the SES isn't lighting up, indicating that it is either burned out or removed, it will cause an E026 code to set.

I guess the engineers did this to insure the bulb would get replaced should it burn out or get removed by someone.

I don't know if this ground was covered earlier in this thread but brought it up in case it hadn't. Anyway...

If your SES lamp illuminates at KOEO then it is NOT the cause of your E026 issue.

 

John F.

[Blue90]

John,

I checked the FSM on p 8A-82-15 under Service Engine Soon Indicator and thought I did in another ECM.

I never thought of something as simple as a bulb.  

With the key in the ON position the SES still does NOT light.

When this first started happening (back in May) I switched out my scratched IPC for a PnP IPC with a clear face.

I have 3 spare IPCs so tomorrow I will (sigh, remove the dash) and switch out IPCs and/or bulbs till I come up with something to report.

Thanks,

Stanley

[DAVES89]

On all my Reattas I no longer screw the bezel back in place. They don't rattle with just the clips and it makes swapping out parts to test a lot faster.

[Blue90]

Thanks for the tip.

S.

[Blue90]

 The end of a saga.  I replaced the IPC today.  The SES light came on with the light show; I went for a drive and NO EO26 code.

Everything appears to be functioning properly.

Thank you everyone who helped me through this trying albeit learning experience.

Stanley

[KDirk]

That's excellent news. I'm glad John posted about the SES indicator. I'd never run into that symptom myself and wasn't aware a bad bulb would trigger an E026 code. Something else to commit to memory now [as if there were any room left].

Good to know you are back on the road and free of malfunctions.

KDirk

[Ronnie]

Just as info for future reference... the lamp test is the last test in a series of tests for code E026 on the page I provided a link to in post #67.

Edited November 9, 2015 by Ronnie (see edit history)

[Blue90]

You're right Ronnie. I remember doing part of the lamp test that included the HOT light.  I guess I missed the last part re the SES light.

S.