Need help

[mustangmike01]

Hay I'm new to the site names Mike. I need some help with my car.
At idle the car sounds like it has cams in it, but it dose not. The idle is moving from 800 to 1,000rpm. It should read 1,000rpm. If I come to a stop, it goes down to 400rpm and I can put my foot on the gas pedal to the floor and nothing. About 20 secants later it goes up to 1,000 and shacks. The car is shaking like crazy. The motor is shaking and the fuel gauge is moving from 25 to 35 psi. It should be at 30psi. I give it a little gas and it smooths right out. What could it be? I think is a one the idle sensors. I drove the car yesterday, I started it up and it ran fine. It stayed at 1,200rpm as it warmed up, no shaking. I gave it gas to rev the motor to 2,000 rpm and took my foot off the gas. The rpms dropped to 300rpm and slowing went to 800rpm and it was shaking. So what do you all think it is?

Here is a list of some of my mods, if it helps.

saleen s/c 10psi, cia, 75 tb, duel msd ignition, aero fuel rails, 42lb jets, bbk 255 fuel pump, diablo chip, jba short headers, bassani hi-flow cat & X pipe, roush exhaust, cobra flywheel, mcloud clutch, 6sp tremeic trany, b&m ripper 3:73 gear

Thanks, Mike

 

[Red2000GT]

I had to read this a few times over to figure out what you said but I think I've got the idea. It sounds like your Mass Airflow Sensor (MAF) is not adjusted to the 42lb injectors. Did you get a new one with the Saleen kit or does it adjust it within the computer itself? The changing fuel pressure is a big clue to that.

 

[twogts4us]

I had to read this a few times over to figure out what you said but I think I've got the idea.

Well, I figured out that ideal = idle, but WTF is shacking?

 

[jcint]

major problems when your car shacks and it's ideal!

 

[mustangmike01]

I had to read this a few times over to figure out what you said but I think I've got the idea. It sounds like your Mass Airflow Sensor (MAF) is not adjusted to the 42lb injectors. Did you get a new one with the Saleen kit or does it adjust it within the computer itself? The changing fuel pressure is a big clue to that.

The only thing I have from Saleen is the s/c and the intercooler. It's been running fine for the last 3,000 miles with the new tune and now it has a problem? I need to fix the problem because I'm selling the motor and the s/c. I need more HP.

Mike

 

[streetstang03]

mine was doing that when the IAC went out. try cleaning or replacing the IAC. its a cheap starting point to see if thats the problem. (~$50 at vatozone for a new IAC valve).

 

[topless98gt]

mine was doing that when the IAC went out. try cleaning or replacing the IAC. its a cheap starting point to see if thats the problem. (~$50 at vatozone for a new IAC valve).

vatozone

 

[mustangmike01]

mine was doing that when the IAC went out. try cleaning or replacing the IAC. its a cheap starting point to see if thats the problem. (~$50 at vatozone for a new IAC valve).

Yep, That's what I thought it was. IAC blow off two moths ago. I was running full boost up a hill for 2 miles. I just added to bolts and it work fine.

Thanks, I will clean it first this weekend to see if that's the propblem