Idle Problems Here- Surge, Lope, Stall, etc...
 

Seems a few of us here are having some of the same problems lately...I was wondering if we started this thread to sort of collaborate on possible diagnosis tips...
My car "lopes" on idle, and pings under load (lean cond.?). Replaced plugs, cap/rotor, fuel filter, and just removed and cleaned the entire intake system, down to lower intake manifold - seems I did all that for fun, it made no diff. Also ran code scanner, nothing. Any ideas?

Check your fuel pressure and the EGR valve for proper seating.

------------------
Capri306, Moderator, The Mustang Works Online
1979 Mercury Capri, 5.0L -- C4 -- 2.73
1987 Mustang LX Notch http://smilecwm.tripod.com/net3/wink2.gif

[This message has been edited by Capri306 (edited 03-18-2001).]

I take it that you probably reset your computer and then let your computer relearn? What's your timing set at?

------------------
351W 89 Mustang GT Convertible

What all have you done to the car?

Is it a factory Mass Air Meter? If not that might be an issue at idle. Injector upgrade? Fuel pump upgrade? Vacuum Leak? Have you swapped out the intake and maybe there is a vacuum leak now? Adjustable regulator? You could have issues with any of these for a lopey idle.

What is your timing set at? Maybe too high?

Just a few things to consider.

Thanks for all the help so far...I should say the car is a stock 95 GT, it is a daily driver. Only "mods" are Gears, Transgo kit, and pulleys (Taylor wires, not really a mod).
Timing is at 10* btdc,
I did not reset the computer because I did have a 628, torque converter issue, that I needed Ford to see (warranty thing).
Don't have a fuel pressure gauge, so I didn't check that, not sure how to check to see if the EGR is seated properly, but as I goose the throttle, I can see the diaphram movin in the EGR housing - like it should.
Also don't have a vacuum tester, so could not check that, but did the poor-man's way of hitting some of the connectors with starter fluid to see if it surged...nothing.

In the past, I have had idle problems similar to yours that were caused by wiring problems. My harness is kind of old and I wasn't getting a good ground to my TPS. The throttle position sensor would randomly be out of range or too high or too low and the idle would jump around. What solved my prob was disconnecting the two large electrical connectors behind the intake manifold (not familiar with the SN95 cars though, but assume you still have these connectors) and cleaning the contacts with brake cleaner, then reconnecting them. This helped with my idle problem and I would suggest doing this on a high mileage old engine. Anyway, just my two cents.

------------------
Michael Black
Quantum Motorsports
Norman, Oklahoma

1988 Merc Cougar 5.0 HO, Ported and Polished E7TEs, 2.25" duals w/ 2 chamber flowmasters, T5 tranny
New E/T!!!
14.626 @ 94.94mph, 2.194 60' time, a little better than last time. Keep in mind this thang is heavy (3590lbs) Finally 14s!!!!

thanks, I have some CRC electrical contact cleaner, too...I will give it a whirl.

Does this problem happen all the time, or only when you are in gear?

If you have a torque converter code and this only happens when you are in gear, I'd be seriously suspect of the converter itself. Like it may be trying to lock up or something. I've seen that happen and kill a car just like not letting out the clutch and coming to a stop.

The "pinging" occurs in gear, under load or WOT. can rev up in Park or N and get nothing. The converter is bad, and being replaced as I type (hopefully!) So after I get it, we will see what changed, I also plan on cleaning all the connectors.