Hello everyone. I need help with my car, here goes. It is a ’90 coupe, m6, 95K miles. I have recently replaced the exhaust (true dual, no cats), done a complete tune up (coil, module, wires, cap, rotor, wires, and plugs), and replaced the injectors (they were bad) w/ new Accel 24 lbs units. I also installed a TpiS AFPR, set FP to 40/38 lbs. A mechanic friend reset the timing. It also has a new chip, burned by forum member. It ran great when I finished, it just had a problem w/ the idle being too high. I changed the IAC valve, which did not help. I have had the plenum off and on the car four times, double and triple checked for vacuum leaks, all to no avail.
Because the water pump was leaking, I replaced it and all the hoses. When I put everything back together the new problem started. At first the car would start and run fine. Then I noticed that if I ran the car and I tried to restart it, I had press on the gas pedal for it to start. Now it has gotten to the point were the first time I try it, it will sometimes start, sometimes not. If it does start, it sputters and seams to miss, until I rev the engine, and then will run OK. If I shut it off, it will not restart. It just cranks and I smell gas. This car always started on the first touch of the key.
I have ohmed the coil, had the module checked at AutoZone, checked the distributor crank sensor, and even replaced the fuel pump relay. Nothing seems to help.

Needless to say, I am beyond frustrated with the car and it’s problems. Any help/ tips would be appreciated.

Randy

 

Did you reset the IAC and all that?

First thing is to set the timing to 6 deg. Next, set the base idle by either procedure below. Then set the TPS to 0.6 V.

Procedure 1:= Hook up a scantool and keep adjusting the throttle blades till the IAC count reads between 20 - 30 counts.

Procedure 2:= Short the A & B Terminals of the ALDL and turn the car on to run but don't crank. Wait 30 seconds and then remove the IAC connector. Shut it down and remove the short. That should close the IAC. Start the car and keep it running till it is warm. Set the base idle till it can run on it's own without dieing out. Shut it off and snap back the IAC connector.

Method 2 is to be used if you have no access to a scantool. Method 1 is the prefered method.

I believe that the earlier TPI cars were set to 0.54V while the later ones were set to 0.6V. I think it is the pre 87 ones that are set to 0.54 while the post 87 ones are 0.6

 

IAC was set per FSM. The TPS on a '90 has no adjustment.
Since installing the new chip, my scan tool will not work, it says the car will not respond.

 

Who programmed the chip for you? Something sounds funny. I have had Lingenfelter write me a chip, Fasterproms and High Hightech Motorsport. All have been able to be read by any scanner.

 

Are there any codes ?? Is the fuel pressure steady after shut down ??
Is the coolant temp sender on front of intake, connected ??
Any fuel in the vac line to reg ??

 

I've had cars with bad EGR valves (stuck open or leaking due to crud in the pintle) give your symptoms.
Hope this helps.

 

Are there any codes ?? No
Is the fuel pressure steady after shut down ??Yes
Is the coolant temp sender on front of intake, connected ??Yes
Any fuel in the vac line to reg ??[/QUOTE]No

ERG has been deleted, that is one of the reasons for the new chip.

 

If you still have the original chip try using it. A custom chip should have NO affect on your scanner....other than to show the changes made. And alot of guys here have deleted the EGR without any driveability problems...I think Vader is one, possibly RRT also.

 

My car is a '90, which is speed density, does not have a MAF. Because of this, when you disconnect the ERG, the computer throws a code, even if everything is gone, like it is on my car.

 

Doesn't matter. What we are trying to test out is the ability of the scanner to pick up data. I, for one, can't understand why it won't datalog

 

I wish I knew why also, I tried replacing the batteries in the unit, nothing seems to help.

I'am not sure if this means anything, but when I plug the scanner in, the fans come on???

 

EGR deleted, custom chip by pcmforless + other mods and no problem with PC and Scanner connected, but this is on my 87...

 

I've had a chip by Fasterproms with no datalogging issues. Guess what? They are modified chips. This is to prevent others from reading what they have done to the chip. Only if you have their circuit board can you read the chip. They have switched things around, shorted out circuits and what not so that the ECM can read it but if you try plug it into a regular reader and writer, it won't work

 

Does anyone think the ECM could be the problem?

 

ECM could be a possibilty, unfortunately most of us have no way of checking them, I know some guys have swapped them out with a friend to check them. When I read your post I was thinking leaky injector(s), but since the pressure holds I think we can eliminate that.
I started a post sometime ago about symptoms of an ECM going bad...most responses were their cars started running pig rich! Which to me means it could flood, and it sounded like your car was flooding at least at first, holding the peddle down to get it started.

I knew of the issue of an EGR delete causing in some cases the computer to throw a code, but most guys said it didn't cause a driveability problem.

 

Rick,
I am going to post the question about the ECM over in the Scan and Tune section. I have changed out or checked just about everything I can think of. Your note that cars w/ bad ECM's start to run rich really seems like what the problem is. I have heard that if you jump the A and B ports on the ADl, and the fans come on (which mine do) the ECM is bad, or going bad.
Comments anyone?

 

The fan should come on when in diagnostic mode, it's not a sign of a bad ECM.

 

What type of scanner and/or program are you using...handheld, laptop?

I am using TunerPro RT with Moates cable and converter. The converter has a switch on it that can be switched for scanning or diagnostics. The fans along with other sensors and relays will come on when trying to pull codes but not when scanning until the engine has reached the the "fan cut on temp" in the chip.

 

I have an Auto Xray hand held scanner. I just took out the Moates adapter and custom chip, and put the stock chip back in. The stock chip was on the adapter the wrong way, I think. I guess that would not let the scanner work?

Pretty stupid, huh?