bart1

I have a rough idle on my 85/2 944. Last night it seemed okay, but it has a rough idle again today, especially when I am braking and in gear. Last night I put in a K&N filter, new Bosch copper plugs (I did not check the gap, all looked good), and a new Mahle fuel filter. Plug wires seemed good (secure connection). Should I replace the distributor cap and rotor? What else?

-Bart

brrt50cal

Cap and rotor are definately a good idea when doing a tune up. Mine idles rough because it needs a tune-up but I can't remember off the top of my head what a rough idle in gear would be.

HY M8NC

You should have bought my car Bart. LOL

What is the idle like? Look at the tach-does it dip too low? What are your symptoms? A rough idle could be motor mounts, or too low of an idle. Get back with some particulars.

I'm goin home now-strep throat

bart1

I haven't ruled out your car yet, Ben! I am going to get this one fixed up good and find somebody that wants an auto. Just hang on to it

The tach doesn't really dip that low. It idles around 1k and dips just a little when it "stalls". I asked in a previous post and they said idle should be 840. The oil pressure gage is bouncing and when the check engine light comes on, the low oil pressure indicator does as well. There is planty of oil and I have not changed it yet. Think I should switch to synthetic after 93k on dino? It has a small leak now, I think the syn would just make it worse.


Rough idle in gear = it's an auto I will get another cap and rotor. I guess after that would be plug wires.

-Bart

emilysgranny

You might have a vacuumn leak. After working on the engine it is to easy to bump a vacuum line and break it or pull one off.

HY M8NC

Good call on the vacuum leak. That is something to check. Also good call on the cap/rotor. My car idles about 950, which keeps the cam lope from rocking the car. I don't know what your idle should really be-but I would consider bumping that up a hair...do you know where that adjustment is?

Keep posting back after these changes-we'll get it ironed out.

bart1

I can figure out the idle, not sure for now. I did find a Haynes manual yesterday at Auto Zone.

I'll look/feel around for the leak, but I am not sure how else to check.

-Bart

HY M8NC

On my old musclecars, I would spray a fog of starting fluid at an area that I suspected a leak. If a vac leak was present, the idle would go up when I sprayed. (Pulls the flamable liquid into the motor)

If you or your car blow up, it's not my fault

I don't know of a better way than just visually checking each hose-and location. Screw the Haynes. It's really only good for holding a door open, or painting on. There are guys on this list that have factory service manuals who can burn you a CD-look through the archives.

indiana_86_944_turbo

fill a small little spray bottle full of soapy water and use that to spray for leaks. the soap bubbles will show if you have a leak.

scott

jabbadeznuts

And with out th potential for a rather large boom!