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Ask GM Tech (Cam) Your Own Question
GM Tech (Cam)
GM Tech (Cam), Chevy Technician
Category: Chevy
Satisfied Customers: 15133
Experience:  GM Grand Master Technician 2007. 14 years experience.
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I have a 1994 Chev Blazer Silverado with 350/5.7 motor and

Customer Question

I have a 1994 Chev Blazer Silverado with 350/5.7 motor and TBI. It starts right up and idles OK unit it gets warm. After that the idle is very rough, especially in gear at a stop light. I replaced the engine temp sensor and IAC module. I've tested the EGR and pretty certain I also tested the TPS. I hate to keep throwing money at parts, but folks on-line are saying anything from TBI Fuel regulator, fule pump (it gets up and goes when you step on it) to MAP sensor and even the ECM. Any ideas? Also read something about the intake gaskets failing on these motors. The truck has nearly 200K on it.
JA: Are you certain it's the fuel pressure sensor that's in need of attention? What about the fuel rail? Have you checked it yet?
Customer: I don't know what to check. How would a fuel rail cause this if it runs fine down the road, just won't idle or go at very low speed.
JA: Are you fixing your Silverado yourself? What have you tried so far?
Customer: Did you even read my first message?
JA: Anything else you want the mechanic to know before I connect you?
Customer: I also replaced the 02 sensor
Submitted: 7 days ago.
Category: Chevy
Expert:  AMEDEE replied 7 days ago.

Hello and welcome!

My name is ***** ***** I can assist you with your question.

Expert:  AMEDEE replied 7 days ago.

Does the fuel pressure leak down key on engine off?