i have an 88 mustang gt ive put exhaust on it and an intake...just little things but in cold weather it back fires it kinda boggs down if its not warm. if i just jump in the car and take off without lettin it warm up and drive a couple miles and stop then take off and push the gas peddel down about half way it will back fire and the car shakes but after it warms up its fine...anyone with any answers or input let me no

 

when was the last tune up done? How many mile on the engine? Is the intake new or has it been on the car a while?

 

First you need to run the codes on the eec. Even if there is not a check engine light. The first things that come to mind are the ECT "engine coolant temp." sensor, the TFI module on the distributor, MAP sensor and or the O2 Sensors. The ECT is one of the most over looked sensors on the EFI setup. It is located in the coolant hard lines on the intake. This sensor tells the computer the what temp. the car is. The temp. reading in-turn tells the eec such things as which fuel tables to run and chooses between open and closed loop operation. If the ECT is giving a false reading, for example: it might be telling the EEC the engine is at operating temp. when it is really cold. The engine would then be running off of the wrong parameters. Also, be more specific when you say "exhaust". What does that include, h-pipe, mufflers, headers, etc? If you just did mufflers yours "cats" could be clogged. If you just did an h/x-pipe then your mufflers could be clogged from fragments from a bad "cat". Also if you go from a 2-1/2 h/x-pipe into stiock 2-1/4 flowtubes/mufflers, this could cause the backfire.

 

i have an h pipe and when i did the exhaust i put new flow master super 40's on it and how would i check to see if the ect was bad

 

 

Oh yeah you have to open it up all the way for best results.......

 

also, back pressure may be playing a role in this problem.

 

was this problem solved?