ONGOING E026 SEARCH

[Guest 89 Maui]

i have been searching for whatever is causing my E026 on my 89 for over 8 months. I have gone thru the test mode and all relays are activating, dunno about the TCC in the transmission but it does lock when the TCC is lit. I have cleaned all power and ground terminations. Last weekend I installed a new EGR valve.

Yesterday I was replacing the gasket on my oil pan and I looked over underneath the windshield washer resevoir and I found the Purge Cannister. Today I attempted to get to the cannister, what a task that is and I still haven't got it out.

I have two questions about that general area. When I was attemting to take out the bracket that the relay solenoids box mounts on I found a module mounted on that bracket and it mounts on that support and sits up against the wheel well. I am wondering what that module is.

I checked on Rock Auto and Advance Auto web sites for a replacement purge cannistor and neither has one but Rock Auto sells replacement filters. I assume the cannistor can be opened and the filters can be replaced, is this the case.

My E026 is intermittant and goes away within 15 seconds. Last night I took it for a test run, to see if the pan gasket fixed the leak, and on previous test runs when I go down into a ravine area the engine is running strong, but when I go up the otherside of the ravine the E026 pops and goes out 15 seconds later, but the engine never loses power. I went into the ECM DATA and selected each input to see what could be activating the E026. The only input that had a possibility was the 02 sensor and only twice did the 02 get down to 2 and 3 reading and then pops up to 60 to 70 and that was out of monitoring it 5 times. I installed a new 02 sensor last fall I also checked all the oher pertinent inputs with no real probability of causing E026 to pop up.

I also flexed as many cables in the engine compartment while testing the output solenoids to see if there was a bad conductor with no avail.

Which is why I am looking at the purge cannistor, the hoses are connecting good with no cracks, but could the problem be with the purge solenoid?

I don't think this has anything to do with the E026 problem, but why does my diagnostics for IGN CYCLES read "0"?

Thanx for the help or suggestions, I want to get rid of E026 before we go down to Concord.

[Guest Kingsley]

'89 Maui - the part that you have described is the Headlight Control Module and is integral to the opening and closing of your headlights. It does not have any other application.

It is an item that seldom goes bad but it has been known to happen. There is no new replacement for it, either OE or aftermarket, so it is not too out of line to have one as a spare. I do not that the exact cross over but there are some Pontiac Fieros and perhaps Sunbirds, that have modules interchangeble with the Reatta - and some that are not.

Padgett, or others, can probably tie down the specific interchangeable modules for general reference purposes.

Aside to Ronnie - once the crossover is properly ID'd, you may wish to add note of it to your Journal.

Kingsley

Member AACA, BCA and Reatta Division, BCA. See me in the Resouce Section.

[Ronnie]

I would be happy to do that.

[D-a-n-i-e-l]

Code E026 hmm programed out of my ECM when I did thmmm quad something or other...... tried to fix it for year or so. Finaly I had it programmed out when I did the sc swap. It never caused any unwanted performance in my car and I never found the cause, I am pretty sure it was in the ECM sensing itself.

[Guest 89 Maui]

DANIEL -

Ronnie pointed out to me in the service manual about the purge cannistor and in that section it pointed out if one of the lower lines is wet to replace the cannistor. Well one line is wet with gas. I hope this fixes the E026.

Thanx

[NCReatta]

I have this problem intermittently with my '89 also.

I haven't had it for probably 2 months and it popped up again yesterday evening (after driving the car 100+ miles that day with no problems).

Beats me. I haven't noticed anything negative coming from it.. I just ignore it.

[Guest Mc_Reatta]

You can use the ECM Output diagnostic functions to single out what is causing the E026 fault.

Scroll thru EO01 to EO10 and listen under the hood for each of the relays or solenoids to click. Except for the two lamps it controls, the Quad Drivers doesn't really know if function called for actually works or not, just that the voltage of the control circuit reacts properly to the command.

If the EGR valves or TCC solenoid don't produce the desired effect on the engine operation, E039, 63, 64, or 65 will set.

[padgett]

Could also be a fan relay, can use overrides to test everything, one at a time.

[Guest 89 Maui]

padgett -

Do you know why when I select IGN CYCLE in ECM INPUTS just reads "0"?

Woody

[Barney Eaton]

One Reatta I owned had a "gas" smell that turned out to be a disconnected hose at the canister. (no codes were set) after reinstalling the hose twice, I had to add a section of hose because the old hose and vibration were causing it to come off.

If you need a replacement canister, Riviers will have the same part.

[jonlabree]

Has anyone come up with a way to eliminate the canister system?

[Roadster90]

I have had the 26 code for several years now and would love to know the exact or most common reason for it. This is a good thread and hope it continues until exacting resolution/s are discovered or problem/s are solved...

thanks,

Nic

[jonlabree]

What's the worst thing rhat could happen if you bypassed the vapor canister?

[wws944]

What's the worst thing rhat could happen if you bypassed the vapor canister?

Here in California, it could fail smog testing. My Suburban actually flunked last month because a little rubber elbow connecting a pipe to the vapor cannister had deteriorated, and the tech flunked it on visual grounds. We used a little piece of fuel line as a temporary fix. The rubber elbows are NLA from Chevy. So I found a couple of them at the local Pick N Pull, for a proper fix and a spare.

[Guest Mc_Reatta]

Probably just that you would smell the odor of gasoline that would escape from evaporation of the fuel in the tank especially on a hot day.

Doubt it would have a great affect on mileage or be enough to explode unless there were other factors involved.

[jonlabree]

What I meant by bypassing the canister, was, to connect the vent line right into the intake manifold, where it goes after the canister, so there would be no fumes.

[Guest Mc_Reatta]

That would introduce a vacuum to the gas tank and add an unregulated air / fuel source to the intake. Would expect issues with idle and wonder if raw gas could be extracted from the tank when topped off or overfilled.

[jonlabree]

That is possible. I think I willtry it and see what happens. It's either that or I am going to try to find a smaller canister.

[2seater]

I eliminated mine several years ago, and it will smell "gassy" under certain conditions as alluded to. The valve from the top of the canister was left connected to the harness and tied to the wiring for support. No codes or check engine light have ever resulted. The vacuum line from the engine was eliminated completely (custom aluminum vacuum block). The line from the fuel tank remains in the same approx. location with a small engine fuel filter attached to allow the tank to breathe and keep dirt out of the system. That line wouldn't like unregulated engine vacuum but it may be possible to route to the air intake near the filter if the pressure depression is very low. Probably wouldn't eliminate the free vapors completely. I don't see any performance advantage to eliminating the canister but it was a expeditious way for me to get it out of the way for the intercooler piping. Low priority but it will probably be reinstalled somewhare in the future.

The ECM sees the valve electrically only (if otherwise isolated) and it just snaps onto the top of the canister, so I would believe that is all that would be needed if it is actually the cause for the code.

[Guest 89 Maui]

I was finally able to get the purge cannistor out. Disconnected solenoid and hoses to intake and tank. Took solenoid and wired it to a 12V battery and solenoid activated and allowed me to blow through the valve. Blew air through the intake hose and heard the air entering the intake. Blew air in hose to the fuel tank with some resistance but suctioning fumes was easier. Turned the cannistor upside down and no fluid came out. Reinstalled purge cannistor which is working properly.

Took her out for more test driving. At 45 mph I could feel the torque converter lock and 2/3rd's up the ravine E026 pops and goes out 12-15 seconds later. Make a u-turn and go back to the other side of ravine with no E026. I finally decided to try going up the ravine at 35 mph and felt the torque convertor lock and made it up the ravine with no E026. Repeated the 35 mph and no E026. Tried it at 39 mph with no E026. Then tried 42 mph and E026 pops. So I found that over 40 mph E026 pops but not under 40 mph.

Is there a condition in the rpm or mph sensing that might be in conjunction with the TCC that could be popping E026 at 40 mph ?

I haven't mentioned the interstate driving but E026 can stay on for as long as a mile but will go out when I start to decrease the mph.

I have checked all of the solenoid tests and lamp tests and I just can't hear if the TCC activates but when I drive I feel the TCC lock.

When I go into diagnostics to watch the TCC, I can go any speed up the ravine with no E026. After I get to the top I will pull over and exit diagnostics then re-enter and find no E026 history. Is this possible that diagnostics ignores the E026 from activating or is this normal ?

Thanx

Woody

[Guest Mc_Reatta]

Should be able to faintly hear the TCC solenoid click when cycled by EO01, but if you can't, do you have a DVM ot test light? You can monitor the voltage between pins A and D on the TCC connector to determine if the pulse is getting thru. Disconnect and attach the probes between A and D. Should get 12 volts when turned on and 0 volts when off.

If the TCC didn't work you should get an E039 code along with the E026, so I guess your TCC is functioning.

There is no connection between RPM and code E026, but there is with code E039.

If your displaying ECM data on the CRT while driving and monitoring the TCC status via the little triangle, I would think code E026 would still set.

[Guest 89 Maui]

After checking out all the inputs that cause E026 to activate, I found that you have to prove that each input is working and then through the process of elimination bring it down to the one input that can be causing the E026 code.

For my problem I had it down to 2 items purge cannistor and TCC.

I removed the purge cannistor and applied 12V to the solenoid and the valve opened which would simulate the solenoid/valve was working OK.

That left the TCC. Once I found what connector had the TCC coming into it, I disconnected the connector which was on the radiator side of the tranny. I then used my ohm meter and measured the resistance of terminals A&D leading inside of the tranny. In one direction I measured 4.5 ohms. I then reversed my leads and also read 4.5 ohms. According to the FSM there is a reversing diode in parallel with the solenoid. The purpose of the reversing diode is to cause eddy currents to allow the solenoid to activate at a reduced speed of activation. This accomplishes two things - 1. Reduces the input current to activate the solenoid slower rather than " slamming the solenoid " with higher current. 2. Prevents the slamming high current from causing a spike in the electrical system that could inter-react and cause problems with other components such as the ECM & BCM.

A defective solenoid opens in over 95% of the time and rarely shorts, another reason to have the reversing diode. Thus with measuring 4.5 ohms in both directions indicates that the reversing diode is shorted. If the diode opened I would the read resistance of the solenoid coil which would possibly be 2K or higher. With the shorted diode, the solenoid would not activate and without activating the TCC -torque convertor clutch would not activate when the ECM calls for it.

I called a transmission shop and found it would cost $700 to drop the transmission to then install the TCC solenoid. With 112,000 miles and I rarely drive on an interstate, with the exception of driving down to the 2012 BCA meet, I chose to wait and change the solenoid when I need to have the tranny serviced and change it at that time.

However, I would continue to get the E026 code. I looked into my parts bins and found a 12V " reed relay ". I will only use the coil of the reed relay so the ECM thinks it is operating the TCC. The contact of the reed relay will not be connected to anything. The reed relay is about 1" long and 3/8" in diameter. I pulled the wires feeding A&D out of the plastic sheathing protecting the wiring harness, the sheathing is split allowing me to pull the wires out for accessability. I cut the A&D wires about 7" from the female connector and it allows me to hide the reed relay inside the plastic sheathing. This also allows me to keep the A&D wires from the connector inside the plastic sheathing for protection and future reconnection when I have the tranny serviced.

I test drove my 89 and the E026 did not come up and that is the first time I have not had the E026 since purchasing the Reatta a year ago.

Yes the TCC solenoid is not operating but for me it came down to how much highway driving do I do and not spending $700 right now.

It can be very frustrating having the E026 activating but the problem can be found with patience and testing.