[Deleted Account Request]

I had to move the distributor to replace the thermostat, and after everything was done and I had retimed it, it now has a surge on start up and sometimes at idle. I have done the following to trouble shoot it, but to no avail. I have checked timing 3 times, checked the computer for any trouble codes, even though there isn't a check engine light on, nothing there. Checked all vacum hoses, all are connected, and none have any holes. All electrical connections are good. I even checked the PCV valve and it lookes real good, the hose was good to, I even cleaned the PCV pocket the valve sit's in! I also replaced the Idle Air Control motor! still nothing.
I don't think there is any problem with the oxygen sensors either.
The car is an 1988 five liter convertable, with a manual.
Before this I've had zero problems of any real importance , If anyone has any other suggestions or thought's on this, let me know!
Thanks Boys and or Girls!
JIM

[90blacknight]

Are you sure you have no vacuum leaks? Did you recently adjust the idle? If so, you may need to reset the tps. Try cleaning out the throttle body. And you're sure the computer isn't throwing any codes?

[Deleted Account Request]

Nope, no codes, no vacum leaks. throttle body is clean, recently did all that as well. As far as resetting the TPS, how is that done?

[90blacknight]

There is a sticky at the top of this forum that tells you all about setting TPS. Normally you don't have to touch this unless you've messed with the idle. Sometimes the sensor can be bad also.

[meangreen92]

Did you pull the spout connecter when you timed it? You need to, or it won't run right.

[systronic]

Check your idle air control. It's the metal cylinder on the front of your throttle body. Pull it off, take it apart, and spray out all the carbon deposits with carb cleaner or throttle body cleaner. Your idle problem sounds exactly like the one i had. After i cleaned the IAC, it idled perfect.

[Deleted Account Request]

Meangreen, thanks for the advice, Yeah I pulled the connector and timed it, so I know the problem isn't there! Thank's again dude!

[Deleted Account Request]

Systronic, Thanks for the help, but I replaced it as one of the trouble shooting steps I did! thank's again man!

[Deleted Account Request]

90blacknight, Thank dude, I'll check it out!

[The Greek]

If you installed a thermostat that leaves the engine running too cool, it'll throw the computer's fuel trim out sync. Food for thought. ---Chuck

[Deleted Account Request]

Thank's chuck, I installed a 160 degree thermostat. I don't know though, it started surging as soon as I started it up upon completing the job. wouldn't happen that quick?

[meangreen92]

True, but you really don't wanna go lower than 180º. The computer doesn't like it any cooler.
Did you unhook your battert cables, by chance? I've seen cruddy cables cause a surging idle.
Also, how do the plug wires look? They'll surge when they need a tuneup.

[shakerhood]

I agree, a 180 Degree Thermostat would be the Coldest I would put in.

[Deleted Account Request]

Sup Mean, I just replaced the plug wires with Ford racing wires from Team C performance center, Also checked the battery cables a couple days ago, all's good there to.
This car has been very well taken care of corrotion is never an issue with this horse. BUT, I will swap out the thermostat and see if that's where the problem lie's.
In the past 2 to 3 month's I've, Replaced the Idle air control, did a tune up that included: plugs, wires, cap, rotor, new MSD coil. installed a flex a lite electric cooling fan and a 100amp alternator to help off set the load the fan pulls, changed the thermostat, replaced the valve covers, installed new BBK headers, replaced the starter, replaced the intake plenum gasket when it was removed to replace the valve covers, flushed the radiator, oil change including filter, replaced a leaking oil pan gasket. all of this was done over a week or so. There was no surge until I turned the distributor to get at one the bolts for the thermostat housing. I'm thinking, maybe a tps problem, although unrelated, ya never know! Now that you guys know what I know, I'm all ear's.
Thanks Guys!

[90 stock stang]

Just a small thing to check but any wires at all in the area of the distributor that you may have streched or moved could have been brittle or had a loose connection to begin with and when you moved the distributor could have started your intermittent problem of surge.