[Short Bus]

It has an intermitant deadspot in the throttle, I ordered a new pedal assembly but now im having second thoughts on that being the problem. At cruising speed engine loses enough power it feels like a fuel pump shut off, so I put a fp gauge in cab and thats not the problem. The power loss is more obvious when cruising in the extreme vs econo program. I havent pulled chip and driven it that way yet, should I try that? Any ideas on what to check? Ive got to get this figured out before I leave tomorrow, not to fond of being stranded on hwy somewhere in western KS or eastern CO

 

[gregrob]

Does it go away immediately when you floor it?

I has a dead spot and inermittent miss and very light throttle and it was the IPR in my case.

If you've changed injectors or anything recently the IPR is suspect as well, it only take a TINY obstruction to screw with it. You might try pulling them and cleaning. I can get you instructions/pics if you haven't done it before.

 

[Short Bus]

yeah it goes away when i floor it. If i had a snap on scanner hooked up what would i look for?

 

[gregrob]

that's a good question.

I would start with ICP, ICP(V), TPS%, and IPR duty cycle.

ICP, and ICP(V) should jump around if it's an IPR issue, as well and duty cycle, although duty cycle tends to move slower.
Compare those values, especially duty cycle, when it does it, and when it's smooth. If duty cycle is way higher when it has the flast spot, that would indicate to me the IPR is trying to close there and can't, or if it's way lower could be building too much ICP?, maybe.

I would think TPS% would go funky at the time it happens too, but I've never personally watched a bad one on the scanner.

hope that helps

 

[Short Bus]

pulled the chip and it didnt fix it. As of now i dont think its tps, just a little bit ago i pulled out of driveway and it took 1-2 seconds to do anything after i mashed the throttle.

 

[gregrob]

wierd....
I would look at TPS% if you can get a scanner. That should tell for sure on the pedal. Sounds like that could be it.

 

[Short Bus]

i dunno what the problem was/ is, but no troubles on the 7.5 hr trip out.

 

[VanAackenBrosRacing]

if you had a pedal problem, you have a check engine light instantly. dont think its that, would have to agree with gregrob, on an ipr issue.

 

[Vengeance]

PCM is bad, we swapped one into it and no more problems.

 

[imelmo]

PCM or tuning?:swordfight:

J/K!

Glad you got it worked out.

 

[House]

my truck did that once, dead pedal then all of sudden it would play catch up and do everything you tried to do why it was dead at once, turned out the ecm was junk!

 

[Short Bus]

took awhile to figure out... now none of you fools buy/ bid on pcms over on ebay lol.

 

[House]

I got ya covered!