Long time reader first time poster so work with me a little bit here please.
I have a 1991 Camaro RS with a 3.1 v6. The car starts and sometimes has a rough idle but the main problem is when i touch the throttle it either completely dies or more often it will drop in RPMs run hard but it will barely stay alive.

List of things replace new very recently
ECU *using old prom*
IAC
MAP Sensor
EGR
O2 Sensor
Distributor
ignition module
All Intake Gaskets
recent Tune up
Air Filter
Fuel Filter

List of things recently tested all by a Professional Tech
All injectors
Fuel Pressure
Ignition Coil
All Sensors
TPS

Please Help me I am completely at a wall right now. The car was running fine, started bogging on throttle but it would come out of it, now it bogs every time i tough the throttle. I cant think of anything either mechanical or electrical.

Before anyone says i should just look it up, i have been looking this up for a while over and over. I may have missed something so if you can point me to a link that i have missed that would be great, but so far i have just been replacing parts that they say may be the problem and none have worked.

Thank You

 

first thing i would check is the replacement ecm, also make sure the prom is fully seated

bogging when u touch the throttle is usually not enough fuel on throttle opening
also check the fuel presure at idle and also with key on and engine off

could also be a vacum leak on the manifold gaskets u just installed

 

also check that u didnt plug the pickup coil on the ignition moudle backwards

 

How do i test the ECM and i have checked the PROM seating. I will check it again just to make sure.

If push comes to shove i do have another 91 RS with a 3.1 ecu/prom 350 miles away and I will try to swap out as soon as i can get it there.

None the less the ignition coil is correctly wired up

How do i check the ECM, i do not have a OBDI tester here so it will have to be done on the cheap.

 

Ok, today i check the prom seating. I undid the battery, pulled out the ECU, pulled out the prom checked all the pins, put everything back together with no luck. The exact same symptoms

Any other suggestions. I really dont want to pay for a trailer to get this thing back back home.

 

hey man, to tell you the truth, it sounds as if you replaced everything i can think of that would cause this electronically,,.. i had the same problem when i replaced the plugs in my car, (1992 firebird 3.1) and i neglected a distributor replace when i did the plugs... plugs pulled too much power from dist. but i didnt know it. i moved to fuel. replaced filter(which was filthy...) and without knowing it, introduced an air bubble in my fuel system, after i figured it wasnt fuel, i replaced distributor by someone elses suggestion and it ran better but still bogged... then someone at autozone suggested a malfunctioning fuel pump, so i tested pressure at the rail /w/ fuel press. tester.. 33 psi.. purged valve and tried again. but when i hit the purge button to release pressure from the tester, air came out instead of fuel.. did this 3-4 times, fuel pressure increased each time, as more fuel than air came from the rail.. when i built up to 47 psi, i started the car and it ran like a champ ever since.. srry for making you read so much, but it really could be as simple as that, atleast it was for me, hope this helps..

 

Thanks so much for the help so far, i have a new symptom

I actually have 2 91 Camaros with a 3.1L in it and i tried swapping the ECU, each kept there origional Prom. The the Camaro I've been having problems with actually immediately came out of it and ran like a champ. I drove it around town then stopped at the store. When i cam out of the store the car started acting like it was extremely low on power, it got worse and worse as i tried to limp it home and how it seems to be acting just like it was before the ECU swap.

I am going to return the ECU that i had installed before and I'm going to see if my car is just burning through ECUs. This is such a weird problem. It is almost making me want to go back to the easy carburetors.

 

open the ECU n look for burnt marks on the board.
it can help find the problem by what section it is, if so.

 

If it burns through the next i will, thanks for the idea. I dont want to open the current ECU because im going to bring it back.

 

Ok i got the new ECU and it did not change anything. There are no burn marks in any of the old ones so i am lead to believe the car is not burning them up. I will continue to try and find any problems but any ideas you guys may have would be useful as I am running out.

 

I just had issues with my son's 2.8. Put new injectors and intake gaskets and a few other items in. Ran worse when we were done. Bad idle and terrible throttle response and backfire in the intake. Turned out to be a plugged cat. Just thowing it out there. Took me two weeks to figure it out.