Hello everybody!

Here I am again having trouble with my 93 SSEI which, for all that don't know the story was a salvage vehicle brought back to life. Runnig great for over a year 'till now.
Here'* some relevant data:
Bin# 1G2HY5214P1254902.
Has new radiator, flushed today, new coolant, 180 stat, new O2 sensor, new crank sensor, new cam sensor, fans connected directly (allways on), cat has been removed.
I've seen a lot of posts for overheating but, execpt for one guy in N California, everyone else lives in a cool weather place. We have an average of 112 during the day (43C) and 90F at night.
My car is really hard to start. I must crank it long and give it gas to start. It then catches on but idles super roughg until I rev it up past 3500 rpm. Then it settles. Temp rises to just bellow 200 in iddle (not moving) within 5 minutes. Driving over 2000 rpm will send the temp near the red within 10 minutes. Don't even think about running the AC.
This is why I flushed the rad, replaced the stat, and the crank and cam sensors.
To no avail.
Also, I can only get 160 miles out of a full tank. (Yes, I've checked the tank and it'* not dented. It holds full capacity)
I don't have a OBD I scanner but I did the procedure for reading the codes as described on Techinfo and it only gave me a code 26 = Quad Driver "A" Failure.
I'm stumped! Don't know what else could be wrong. Although I'm sure my spark plugs get fouled by this misfire. (I clean them regularly).
I think a vaccuum hose might be at fault, but where are they? Or maybe the EGR valve and/or its solenoids.
Please don't tell I have a cracked head!

As always, I appreciate any help you can provide me with.

I suspect your rough starting is unrelated to your running hot.

Can you have your catalytic converter checked for backpressure? I suspect it is the culprit for the high temps, particularly if the wide open throttle (WOT) is affected more when hot than not.

Your rough starting is likely a throttle body/IAC (idle air controller) issue. Or just a general tuneup.

Consider a full tuneup, check your fuel pressure, and clean your throttle body and MAF using the procedure in Techinfo.

Hi!

Thanks for the info.
I have removed the cat converted just to check this.
Still rough and hot.
Smells rich when starting and threw a code 26.
I will clean the MAF. But, what do you make of the code 26?
EGR needs cleaning or maybe a have a vaccuum leak?
I couldn't find a diagram for the vaccuum hoses.
Have one, anybody?
Also, the EGR cleaning is in the Techinfo, right?

While I don't have a vacuum diagram for your year...I did find my routing on the radiator support. Maybe your'* is there as well...I'm unsure.

Otherwise..simply look over all the small rubber hoses on your motor and look to the driverside fender area..there'* a couple over that at the charcoal canister.

Seems like you've done everything possible for the overheating problem. Could the sending unit & or gauge be off? Has the engine ever boiled over?

The gas mileage & having to clean the plugs has me suspecting the ignition system. Remove the coils, check the resistance & report findings. What spark plugs are you using? Have the wires been changed recently?

Here'* a link on how to check the coils.
http://www.bonnevilleclub.com/forum/...e=article&k=33

Sorry it took so long for me to respond. My pc got a virus. Now it'* fixed.

Here'* what Autozone system says about code 26. I don't know how to place it in the "tech" part of the forum. And, since this is the code I got from my car, here it is.

"Troublecode 26 means that the electronic control module (ECM) has experienced problems in the grouped triggering "Quad Driver" (QDM) cicuits.

The powertrain control module (PCM) provides a ground for several contrlled devices. Trouble code 26 means that an error occured on one or more of these circuits.

It is likely that other trouble codes will also show along with code 26. If codes 38, 39, or 56 also show, service those codes first.

With ignition on (engine not running), lookto see that the "TEMP" light is lit. If the light does not come on, check the "TEMP" light circuit.

Jumper tha "A" and "B" (TEST) terminals in the diagnostics connector (ALDL), and turn the ignition on. This will signal the PCM to ground the affected circuits.

Unplug the harness connector at the canister purge solenoid, and connect a test lamp between the harness terminals with the dark green/yellow and pink/black wires.

The test light should come on. If it did not glow, check the harness terminal with the pink/black wire to ensure it provides battery voltage with the ignition on.

If the test light did not glow, and the pink/black wire was ok, check the dark green/yellow wire from the canisterpurge solenoid to the PCM green connector, terminal "C5" for a short/open circuit.

If the canister purge solenoid is suspected, check it with an ohmmeter. See component testing - Canister Purge Valve.

With the test lamp still across the harness terminals, remove the ALDL jumper. The test light should go off. If it didn't and the wires are ok, it is likely a bad PCM.

Unplug the harness connector at the low speed cooling fan relay, and connect a test lamp between the harness terminals with the gray/black and brown wires.

The test light should turn on. if it did not glow, check the harness terminal with the brown wire to be sure it provides battery voltage with the ignition on.

If the test light did not glow, and the brown wire was ok, then check the gray/black wire from the cooling fan relay to PCM green connector, terminal "C4" for a short/open circuit.

With the test lamp still across the harness terminals, remove the ALDL jumper, the test light should go off. If it didn't, and the wires are ok, it is likely a bad PCM.

Use an ohmmeter to check across the cooling fan relay, terminals (2 and 5). The ohmmeter reading should be greater than zero ohms, but noy infinite ohms (open circuit).

Check the drivers information center'* "DIC" fuse and make sure it'* not blown.

Unplug the harness connector at the "TEMP" lamp, and connect a test lamp between the two harness terminals (both have pink/blck wires).

The test light should go on. If it did not glow, check that one of the harness terminals with the pink/black wire has battery voltage with the ignition on.

If the test light did not glow, and the pink/black wire was ok, check the other pink/black wire from the "TEMP" light to the PCM green connector, terminal "C7" for a short/open circuit.

With the test lamp still across the harness terminals, remove the ALDL jumper, the test light should go off. If it didn't, and the wires are ok, it is likely a bad PCM.

Visually inspect the lightbulb to be sure that it has not burned out. Replace bulb as needed.

Unplug the harness connector at the torque converter clutch solenoid (TCC), and connect a test lamp between the harness terminals with the tan/black and purple wires.

The test light should turn on. If it did not glow, check the harness terminal with the purple wire to be sure it provides battery voltage at all times that the brake pedak is not depressed.

If battery voltage was not found in the purple wire at the transaxle connector (terminal "A"), check the brakelight switch to be sure that it is prperly adjusted and working.

If the test light did not glow, and the purple wire was ok, check the tan/black wire from the TCC solenoid to PCM green connector, terminal "C6" for a short/open circuit.

With the test lamp still across the harness terminals, remove the ALDL jumper, the test light should go off. If it didn't, and the wires are ok, it is likely a bad PCM.

Use an ohmmeter to check across the TCC solenoid terminals. The ohmmeter reading should be greater than zero ohms, but noy infinite ohms (open circuit).

The QDM uses an internal circuit braker so that if a controlled component or circuit is found to be short cicuited, it does not typically affect/damage the ECM."

That'* it! Verbatum.

Of course now we know what the "Quad Driver" controls. Still have to look up the procedure for checking the purge cannister solenoid etc.

I cleaned my MAF sensor, replaced my air filter, checked vaccum lines, (I don't remember who asked but I'm running standard ac/delco plugs).
Starts a little better, but still won't do it on its own. I have to give it gas to start, and then it starts very rough and with a heavy gasoline smell (flooded).
I checked the pressure at the rail and gas spurts out. I don't know how strongly it should come out. But I let it flow to nothing, then turn the key and tested again and it was pressurized again.
I bought the fuel pressure regulator just in case but I have no idea how to remove it. It loojks like it takes a special tool to remove it.
Could you please tell me how to replace this? Or point me to the rifght topic?
I couldn't find it in the search anywhere..

Thanks for putting up with me and I hope this helps.

Have you done a compression test? A burnt valve will cause a rough idle.

Code 26 and Quad Driver.. Sorry...we don't all know what it controls.

If it'* the quad for the evap purge and boost soleniod.. consider that the BCS is possibly gone even though it seems to function 100%. We've seen this occur and drive people nuts.

Fuel pressure. Please..don't waste any money on a regulator.. check the actual pressure with a gauge. Using your finger tells you only that fuel is getting to the rail.

O2 sensor is old, new or unknown?

The reason we are asking is to understand better and help you fix it while keeping costs to the lowest amount possible.

All all 6 plugs getting fouled?

Thanks for the input!
OK. Answers to your questions:

No, I have not performed a compression test, but all the mechanics that have seen the car seem to agree that the engine appears to be in good shape.

No, the plugs didn't even get "fouled" (covered in carbon or burnt) But I replaced them just the same since I was checking them.

The O2 sensor is about 6 months old. I replaced it when I started the troubleshooting. I also removed the Cat.

What kind of gauge can I use to test the fuel pressure ? And what should the reading and procedure be?

Remember that it'* guzzling gas. It'* giving me roughly 120 miles per tank.