Idle Woes

NJTBIRD89

Registered User
Hey Everyone! It's been a while and I'm at it again
I need to pay my membership dues...lol:eek: :eek:

OK... Riddle me this CLUB?

My 89 SC has an issue with Rough Idle in the mornings. Well I'll explain... at start up car seems to be fine then anywhere from 2 to 10 minutes (when it gets to operating tempature it start a very rough idle

She's almost trying to smooth out but it takes another 15 minutes for her to smooth out... so i thought it might be the IAC (NOPE) switch that one out with a fairly new one (same problem) ... thought it was a MAF issue switched that out same problem... even before installing I have checked the Crank Sensor (that's new... have a BHJ harmonic balancer with 0 balanced underdrive pulleys recently installed

I'm thinking 02 sensors a stuck egr ...car was running lean with a CEL (but we found a ground issue that cleared that up on the o2 sensor) ....... Old a$$ EEC iV or dis issue


I'M SO READY TO GIVE UP ON THIS CAR!!! I CANT ENJOY ONE SUMMER WITHOUT AN ISSUE....LOL!!!!!!!!
 
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NJTBIRD89 said:
Hey Everyone! It's been a while and I'm at it again
I need to pay my membership dues...lol:eek: :eek:

OK... Riddle me this CLUB?

My 89 SC has an issue with Rough Idle in the mornings. Well I'll explain... at start up car seems to be fine then anywhere from 2 to 10 minutes (when it gets to operating tempature it start a very rough idle

She's almost trying to smooth out but it takes another 15 minutes for her to smooth out... so i thought it might be the IAC (NOPE) switch that one out with a fairly new one (same problem) ... thought it was a MAF issue switched that out same problem... even before installing I have checked the Crank Sensor (that's new... have a BHJ harmonic balancer with 0 balanced underdrive pulleys recently installed

I'm thinking 02 sensors a stuck egr ...car was running lean with a CEL (but we found a ground issue that cleared that up on the o2 sensor) ....... Old a$$ EEC iV or dis issue


I'M SO READY TO GIVE UP ON THIS CAR!!! I CANT ENJOY ONE SUMMER WITHOUT AN ISSUE....LOL!!!!!!!!

Pull your plugs and check for traces of antifreeze.
 
Sounds like a seeping head gasket to me.

Do what Dave says Check plugs. Also if it looks very clean,like
steam cleaned you have a seeping head gasket.

But first Look at the overflow tank and in the radiator. If you have small
black specks in the anti-freeze & radiator cap. You have a seeping head gasket,
that will be soon be a blown head gasket.

Good luck Randy
 
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and it continues

Guys,

I have a new engine in... the antifreeze is fine not loosing any fluids there are no bubbles or black spots in the coolant... in fact when i first got the car back from putting the new engine in it ran like a champ then on one day i start the car and drove it then it just start doing this but cleared up
then it did it again the next day so had to let it run for about 20 minutes then it cleared up ok to drive for the most part of the day

I'm thinking about a check list:
Stuck EGR, (it threw a code for that)... :confused:
O2 Sensors (in the past it ran lean) that was a ground issue:confused:
DIS Module (never changed it ):confused:
Plugs and Wires:confused:
Fuel Pressure regulator:confused:
Fuel Filter: :confused:
Fuel Pump: :confused:
EEC IV :confused:
BAP Sensor :confused:

Motor Mounts (But i just put new ones in when the engine was out) Solid Rubber ones from SCP

Just want to get this solved before I decide to really beauty her up
 
might be ur DIS module, thats how mine acted once, it would misfire, but it would act right, then it would do later on, changed the DIS, and never looked back, try taking off the DIS module and cleaning it, and reapplying a thin layer of thermal paste... see if that helps.
 
RadiumSC said:
If reapplying the heatsink doesn't work, I believe Autozone can test the DIS to see if it's good.

I was thinking just that //// you know i have spent so much time trying to figure this out that i could have bought someone elses car :mad:

every summer it's a project i just like to turn the key and feed my need for speed (well just drive it without the random woes:D
 
i ahd the same problem with my 90sc

so i went down the list skipping crank sensor.

1. Arctic silver heatsink grease under DIS(check for you)
2. new fuel filter, oil change...
3.you shold only run 91+ octane gas.
4.injectors cleaned...try it, worth $6, i used seafoam, or lucas
5. unplug your MAFs if its not working there shoudlnt be a change in idle, get a new one.(check for you)
6.i never knew when the plugs were changed last so i bought app764plugs, and motorcraft wr4104 wires.
cleared my problem right up.

PS. i also have a quick release terminal on the (-) side of the battery that would come loose, and at an idle the car felt like ~~~~, but drove okay, then i put it on correctly, no more problems.
 
DIS Module

This happened to me about two months ago. Start up fine, drive about 10 minutes then the idle would be very rough, check engine light comes on, no raw fuel smell. Then sometimes while driving it would actually fix itself and run normal. I changed the DIS module (Autozone: $135.00 w/ Lifetime Warranty) and the problem and codes went away. I changed the O2 sensors, Plugs and cleaned the MAF Sensor before I did all that and wished I would have did the DIS first.

Good luck.

John
 
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