New to a Zetec, has rough idle, normal?

[tjbugs1]

The Wife just got her dads 95. I noticed it has a rough idle when in drive. It dose not die, comes close though. If you put it in neutral it smoothes out. Just wondering if this is normal for the Zetec or not.

Thanks!
- Tyson

[95merc-mystique]

I would say that is not normal. Or more properly that is not good. A lot of these Zetec experience a rough idle, but in all cases something is wrong. It should tick over very smoothly.

Start with the easy and free ones.
Pull the codes and see if anything comes up
Check Air filter
Check Spark plugs
Check fuel pressure
Make sure the IAC is working properly (use search, there are a lot of threads on this one)
Make sure the crankcase breather hose is not plugged (attaches to valve cover)
Check for vacume leaks
Visually inspect the timing belt
Check compression (would only be free if you have access to the tools)

If they have never been done, do the easy replacements
Replace air filter
Replace fuel filter

Then check the harder things
Check the charging system
Check for good spark
Check for clogged injectors
Check for bad MAF (try borrowing someone elses

Hopefully you find what you are looking for there.

[95merc-mystique]

The Wife just got her dads 95. I noticed it has a rough idle when in drive. It dose it die, comes close though. If you put it in neutral it smoothes out. Just wondering if this is normal for the Zetec or not.

I just though of something else that is really easy to check. I though of it because I currently have the same problem. Check your battery. A simple voltage tester can tell you if that is the problem. Put that baby in 20V mode and poke those terminals, it should read somewhere around 12V (higher is better in this situation). Mine currently reads 2.4

I could charge it but I have good reason to believe it is actually dead.

[Tony2005]

... I noticed it has a rough idle when in drive. It dose it die, comes close though. If you put it in neutral it smoothes out. ....

Check engine/tranny mounts. Zetecs are very prone to this.

[swissfrank]

Yes what Tony suggested is the major cause for a harsh and shakey idle. I also had a horrable death shake upon idle, but then I replaced all 4 mounts ( Center Transmission Mount, Rear Transmission Mount, Front Engine Mount and the Right Engine Mount ) Total came to about $210CAD for the mounts, two of them are inserts and cheap, but the center transmission mount is a real hard one to find and expensive. My old mounts were completely torn apart from my driving and were just letting the engine flex around endlessly. After replacing these I also did the timing belt and re-timed my engine, and it was purring like a kitten.

Frank

[dunhamjr]

Yes what Tony suggested is the major cause for a harsh and shakey idle. I also had a horrable death shake upon idle, but then I replaced all 4 mounts ( Center Transmission Mount, Rear Transmission Mount, Front Engine Mount and the Right Engine Mount ) Total came to about $210CAD for the mounts, two of them are inserts and cheap, but the center transmission mount is a real hard one to find and expensive. My old mounts were completely torn apart from my driving and were just letting the engine flex around endlessly. After replacing these I also did the timing belt and re-timed my engine, and it was purring like a kitten.

Frank

Ok the engine may rattle around a bit because of the engine mounts but I hardly see how the actual idle would be affected.... if the car feels like its going to die (low idle speed and loping) then engine mounts are not the issue.

Its likely that you car's idle was more positively affected by the new timing belt and re-time than the engine mounts.

I am pretty confident about this because I have a similar situation in my zetec, and the engine mounts are not the issue. The car starts fine, the engine does not rock and sway too much... but when I stop at the first stop sign after leaving my house the idle is so low and loping that the car will often want to die. After about 5 minutes this issue goes away and the car idles fine, in or out of gear.

[jamesmason]

My cars engine mounts caused unusually strange idle, it would idle hard and inconsistently at a stop or when in neutral coming to a stop. when I fixed the mounts, the engine idle performed properly when stopped at idle but still acted up when coming to a stop with car in neutral. This had to do with the electrical system, specifically w/ the voltage regulator not keeping the voltage where it should be (14.5 when the cars running). simply put it was keeping the same resistance for higher rpm's to stop excess voltage even at lower rpms causing the battery to dip to 12 to 12.5 volts while the car was running which the car can still run on, just not efficiently. once the car warmed up the voltage regulator adjusted to rpm level more efficiently and stopped hard idling. the V/R shouldn't do that and is a sign of it going bad. test the batteries voltage while running (if you don't feel comfortable doing this w/ a dmm go to auto zone and they will surely do it.) do it while it's cold the do it after it's warmed up.

[yomanwill]

since it's a 4-cyl. isn't a little vibration at idle expected, and as the revs increase the power strokes come in sequence more often? When you put in into netrual the revs usally increas from 500-600 to aprx. 900-1000

Is the CEL on? I know that when i was having problems with the EGR system it would make my car run very rough in idle.

Same when the fuel filter was cloged.

Smae when a mouse chewed though a wire.

Same when my battery was dead/dying.

...pick your posion

[bigworm]

ive changed so many parts out in my car it still does the same rough idle ive checked and rechecked miles of hoses and so far nothing. The colder it is outside the more rough it idles... so i pray for a warm day lol

[jamesmason]

It could also be viscosity breakdown with the oil and it's just thicker when cold w/ old oil deposits to compound the effect, that could be your culprit. I'd still say test your alternator. you don't even have to remove it, and all that's required is a dmm and a metric socket set for your intake.