High rpm engine problem

[bensett004]

i have the same problem, new pump and plugs, filter changed too. no cats 3in dp o2 sensors tuned out i think? when i got it had a tune already, under lite acceleration it runs fine, the second it starts to boost it falls on its face, no codes unless i let it miss for a couple seconds then i get a missfire code but goes right away, tested coil packs seem to be good.....i can go 0 to 90 fine as long as i dont boost????? im out of paitence and money lol

 

[matt5112]

my car did that, it was the ICM.

second i touched boost it was misfire city.

 

[backinblackgtp]

i dont even know what the ICM is, how can you check it?

 

[windowrattler]

Not sure how it's controled but isn't the fuel pump a dual pressure system for when it boosts it goes to a higher psi or something?

 

[FordMan77]

i dont even know what the ICM is, how can you check it?

ICM= Ignition Control Module. This is the part that sits below all the coils and has the large wire harness connected to it. No idea how to test though besides swapping in a known good one.

 

[backinblackgtp]

so pretty much only way to test is through lots of labor. lol

 

[FordMan77]

Either that or find a known good one and swap it in.

 

[honkbox]

To all on this forum I have a couple of things I would like to say.

First, thank you so much to all of you who tried to help me throughout this thread. That goes for the people who provide this forum. Lots of great info and great users.

Secondly, I finally fixed my problem and wanted to share what I found. When I did the full tune up the guy behind the counter talked me into the nine dollar a piece iridium plugs. He said they were the best thing going. I installed these and didn't think anything else of it. On this forum I did a lot of research and found that every post about tune-ups said to use Autolite 606's on a stock motor. After all the time and other areas I was troubleshooting, I figured replacing the plugs was a longshot, but at this point i was willing to try anything. I replaced the iridium plugs, with the two dollar Autolites and my problem immediately went away. I won't say iridium plugs aren't good, they just don't seem to like my motor.

Once again thanks to all with the support and feedback.:th_thumbsup-wink:

 

[mskram1]

Indubidably true the iridium electrode holds in more heat than the copper electrodes of the autolites so they cause what's known a preignition I used some acdelco stock replacements for 7/ea and they sucked too...