Exhaust changes causes problems

Yep I did. ECM is on it's way monday.

[XfireZ51]

Originally Posted by rogerzr1

I did what you said Pete(pretty cool btw). The car didn't shut off at 75. I decided to take it for a drive with the power key off. It drove like sh**. When I applied the gas, the car shuttered and vibrated for a couple of seconds then smoothed out. My question is even though the car didn't shut off at 75, can the primary fuel pump still not be preforming correctly. Just wanted to see if this rang a bell with anyone. I plan on getting a guage tomorrow and trying what Jeff said to do.

BTW I appreciate everyone's help trying to educate my ignorant a**.

Just re-reading these posts. Sounds like a fuel issue to me but its not the fuel pump or filter. He has backfiring on decel and stumble at tip-in which sounds like a lack of AE. I would suspect TPS or CTS. My $.02.

[rogerzr1]

Originally Posted by Jeffvette

Yep I did. ECM is on it's way monday.

Jeff, just checking to see if you had a chance to send the ECM. I was hoping to possibly get the car running good before the Meeting in AL. I know it may not be the ECM, but it seems like the best place to start before I take the plenum off.

Roger, it's supposed to be delivered tomorrow afternoon I believe.

[rogerzr1]

Originally Posted by Jeffvette

Roger, it's supposed to be delivered tomorrow afternoon I believe.

Thanks Jeff. I will let you know what happens when I hook it up. If it gets here tomorrow I will hook it up then. Thanks again for your help.

No problem, hope to see you in Birmingham.

[rogerzr1]

Originally Posted by Jeffvette

No problem, hope to see you in Birmingham.

Looks like Birmingham isn't going to happen for me.

I changed the ECM and there was no change. I appreciate your help Jeff, I will send the ECM back tomorrow.

With the ECM elimenated as the problem, looks like I will be going under the plenum for some answers.

What is my next step. I had new plugs put in in August, but I am not ruling that out. I have a set of spark plug cables to put on.

What gaskets do I need to get before I start?
What other things like maybe a coil pack or what else?

Again my car stumbles at low rpms. It has been driving better at WOT since I replaced the o2 sensors, but occasionally stumbles there as well.

If I don't figure this thing out before summer I will video the explosion.
(anyone found me a stick of dynamite yet)

[Demps]

What are the plugs gapped at?

[Polo-1]

did you ever check the TPS ?

Does it have a smooth sweep up and down in volts?

[XfireZ51]

Roger,

Have you ever checked the fuel pump clamps like SGS suggested? Lgaff had a similar issue which was remedied by stainless hose clamps.
Or you keep talking about ambient temps affecting the performance.
Have you tried looking at the Coolant Temp Sensor and replacing?
The hesitation sounds like its going lean at tip in and for AE.
Again, a scantool would REALLY help here and save time/effort.