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Shelby5150
04-25-2006, 06:28 PM
Well, I just got my hands on 87 CSX #239!:thumb: Mock_glh rode out with me to pick it up. Got it home and we got to working on it right away.

It's having some issues idling. Here's a description of what we're working with.
2.2 T2 (500 miles on it), unknown injectors(most likely stock), Walbro 255 pump, Accufab AFPR. Need more info?

Here's the problem: The car doesn't like to idle. The idle bounces up and down, going maybe as high as 1500 rpm, then dropping real low and eventually dying/shutting off. If you rev it up, it runs nice and smooth. It seems as if it's having problems controlling the idle.

The first thing we noticed was a vaccum leak to the MAP sensor, but when the sensor was hooked up, it seemed to run worse (way lean). So I grabbed one off my CSXT and it did'nt change anything.

So we hooked up a fuel pressure guage and noticed the guage fluctuating. We crimped the return fuel line and noticed a lack of pressure surge. Swapped out the fuel pump with a new 255 Walbro. Did some more testing and noticed the f.p.r. was bad (crushed to raise fuel pressure, gas pouring out the vaccum line) and installed an Accufab. Now the fuel system seems to be fine.

When pulling the connector off the coolant temp sensor, we noticed that it seemed to run a little better/smoother, so i swapped out the temp sensor. It came off my T engine which ran fine until a bearing gave out, but that doesn't mean the sensor is good/bad. Runs the same with either sensor. Unplugging the O2 sensor also smoothed out the idle.

I swapped out the Idle air control valve with one from my T's engine. We also tried swapping out the O2 sensor (with a used one that worked fine previously). The logic module was swapped with an 87 Daytona (171) LM. And it's still FUBAR.

At this point i'm thinking that it's a vaccum leak or wiring problem, but me being a noob still, would love to hear from you! :whip::dancingbana:

87glhs232
04-26-2006, 07:44 PM
Have you removed the TB and cleaned it? They love to gum up in the bypass passage and the seat for the control pintle . I had similar idle issues until I pulled the TB and cleaned it inside and out. Be sure to get the back side of the butterfly as well, and slap a new TB gasket on there.

Shelby5150
04-28-2006, 01:43 PM
Well, problem solved! Read more about it here (http://www.turbododge.com/forums/showthread.php?t=115356).
It's worth the read because it's really amazing what was causing the problem!

GLHSKEN
04-28-2006, 02:31 PM
LOL... I had a local guy complaining about a similar issue. Told him to swap to champions.. Issue gone.