idle problem on car

**Kham** · 03-03-04, 08:24 AM

what are some common problems with rough idle on a car. i change plug, wire, rotor. air filter is ok. will do fuel filter this weekend. what else? any sensors? O2 sensors? engine itself? engine burns oil. something is loose in there.

**Honclfibr** · 03-03-04, 08:50 AM

What did the old plugs look like when you replaced them? Plugs are a good indicator of where the problem might lie sometimes...

If you're burning oil, you probably have worn valve seals or piston rings. Might want to check your cylinder compression, if it's very low that could be the source of an off idle...

**Kham** · 03-03-04, 09:10 AM

Originally posted by Honclfibr
What did the old plugs look like when you replaced them? Plugs are a good indicator of where the problem might lie sometimes...

plugs look like crap because couple wires weren't plug in.

Originally posted by Honclfibr
If you're burning oil, you probably have worn valve seals or piston rings. Might want to check your cylinder compression, if it's very low that could be the source of an off idle...

warn valv and rings will cause rough idle? then there's nothing much i can do to fix it but run it to the ground. pretty sure those are worn. but how much?

will take comp. reading as well.

**Kham** · 03-03-04, 09:39 AM

that's the one. problem was there - rough idle. will replace fuel filter and dump one of those injector cleaner in gas tank and see what happened. it won't stall but just anoying as hell when not moving.

**Honclfibr** · 03-03-04, 09:49 AM

Sounds like you've got the right idea so far, starting with the least expensive and working your way up. On a car of that age, all those things you replaced probably needed it anyway...

Yeah bad enough compression can make your car idle bad, especially if one cylinder is really bad, because you'll get inconsistent power delivery. But then, low compression should be felt across the rpm range...besides like you said, if it's your rings probably not worth replacing anyway.

If you've got a timing light, wouldn't hurt to check the timing while you're under there?

Good luck with the filter, it's definitely worth replacing but the filter on every japanese vehicle I owned has been a huge pain in the ass to replace

KB · 03-03-04, 09:52 AM

A vaccum leak will also make your car idle rough. Does it smooth out once you get it going? Is the idle rpm lower then usual when this rough idling occurs?

KB

Kham did you ever get that title?

KB

**Feirax** · 03-03-04, 09:55 AM

Anytime i get a rough idle from a vehicle.. first thing i do is get some dry gas.. and run that through.. dunno if the injector cleaners have the same kind of effect or not.. also check idle speed to make sure its in spec for engine..

_F

**Kham** · 03-03-04, 10:12 AM

Originally posted by Honclfibr

If you've got a timing light, wouldn't hurt to check the timing while you're under there?

have the gun but dont know the spec and if need to short/ground anything first.

**Kham** · 03-03-04, 10:15 AM

Originally posted by rmbbikes
A vaccum leak will also make your car idle rough. Does it smooth out once you get it going? Is the idle rpm lower then usual when this rough idling occurs?

KB

Kham did you ever get that title?

KB

oh yea vacuum.. yep it smooth out once going.

still no title. lawyer is taking too much time and still promise by this summer.

**Kham** · 03-03-04, 10:17 AM

Originally posted by Feirax
Anytime i get a rough idle from a vehicle.. first thing i do is get some dry gas.. and run that through.. dunno if the injector cleaners have the same kind of effect or not.. also check idle speed to make sure its in spec for engine..

_F

it returns to around 750. i think that is correct.

**Kham** · 03-03-04, 10:22 AM

isnt correct timing for getting max performance?

vacuum leak is more likely associated with idle?

real noob questions here.

**Kham** · 03-03-04, 10:32 AM

Originally posted by Kham

still no title. lawyer is taking too much time and still promise by this summer.

you guys wanna make a visiting ride w/ me? i'll do the whacking and you just make sure his goons stayed back.

j/k

**Feirax** · 03-04-04, 01:11 PM

I have two honda accords that both idle around 700-800 rpm and I can't say they're exactly smooth at idle and its completely normal. Bring it up to 900-1000 rpm and they smooth right out.. Pretty typical for an engine imo.

**wastedincome420** · 03-04-04, 01:53 PM

Make sure you check the rubber boot that conects your airbox to the intake manifold... Remove the rubber boot and hold it up to some good light to check for any cracks (be sure to kinda bend it around to see if theres any cracks)

**TheIglu** · 03-04-04, 10:54 PM

If that is the straight 6 in that Supra, then I really don't think i will idle well below 1000 rpms, but thats just me.

**Kham** · 03-04-04, 10:57 PM

Originally posted by TheIglu
If that is the straight 6 in that Supra, then I really don't think i will idle well below 1000 rpms, but thats just me.

huh?

a friend has 84 and it idle perfect.

**skiierx** · 03-05-04, 02:02 AM

Hey Kham, maybe you should move this to another forum! Maybe a supra forum??

I am bustin your balls!!!!!!!!!!

Jamie

**MrX** · 03-05-04, 08:03 AM

I would check the timing first. Go to your local library and see if they have a Motors Manual. It should tell you how to check the timing and if you have to jump out a cooling fan relay or some other sensor.

**Kham** · 03-05-04, 08:47 AM

havnt been to library in awhile. dont even know where it is any more.

i browsed couple autozone stores manual section but nope. ill order it someday.

**need4speed** · 03-05-04, 05:07 PM

Kham,

try going to this site

Car Pros

**Collision pro** · 03-05-04, 06:13 PM

Maybe it's time for a new car.

**Kham** · 03-05-04, 06:20 PM

Originally posted by Collision pro
Maybe it's time for a new car.

that is my new car you dork.

old you new me. no green. saving for bike.

idle problem on car

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