miss at idle
miss at idle Hey guys. I'm having a problem with the 95 TA having a miss at idle. Can't feel it just can hear it. No check engine light. Replaced a bunch of parts mostly because they needed replacing anyway but it still hasn't changed the problem. So far I've done O2's, plugs and wires, injectors, IAC, Opti, coil, water pump. Also kind of unrelated did LT's and ORY, deleted EGR and AIR, motor mounts. Had computer tuned by Madtuner. The car sat for a long time before I bought it and I'm trying to get her 100% to be my daily driver. I haven't driven it yet since I just got it together tonight but before it would also jerk in 6th gear. I'm assuming since it still has the miss it will probably do the same but I'll find out when I can drive it. Looking for any other ideas please!
Last edited by SilverSS07; Feb 13, 2012 at 10:05 PM.
Drove her around for about an hour this morning. Seems to drive great. No jerking in 5th or 6th at low RPM. Still has that slight pop kind of sound at idle. Also running an open Y pipe- I don't know how much I'll be able to hear it after I hook the muffler up. Anything I should check for with the scanner? Everything seemed pretty normal to me but I'm no expert. Coolant temp per the PCM was about 25*-35* higher from what the gauge was reading. I rechecked all the vacuum hoses again the other day. Going to recheck all the grounds and wiring/harnesses today. If I have time I'll do a compression test tonight.
What rpm is the car idling at? Also you said you replaced the injectors, check all the connectors on the injectors. Also you said you replaced the wires, check to make sure they are completely on the plug they can be a pain sometimes.
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Joined: Apr 2011
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From: Deep in the heart of Texas
Check tonight in the dark for any ignition flash from the plug wires to the block or headers. Run the tank low on fuel and fill in up with 93 octane and maybe a splash of octane boost. Have you done any rocker arm adjustments? I'd check the valve lash. Check to ensure all the plugs are tight. That one got me a while back.
Could pop each plug wire off one at a time while at idle and see which cylinder is bad. just don't shock yourself. Once that is determined trouble shooting the problem will be much easier.
Compression test, plug gap correctness, bad plug wire, so on.
Could pop each plug wire off one at a time while at idle and see which cylinder is bad. just don't shock yourself. Once that is determined trouble shooting the problem will be much easier.
Compression test, plug gap correctness, bad plug wire, so on.
Idle is set at 800. It has 93 octane in it now. I gapped the plugs at. 50. They are ngk's. The wires are definitely a pain lol. They are Taylor 8.2s. I'll check them again. I'm sure plugs are tight. Checked them twice. I replaced The coil because The connection was kind of corroded on the one it had. The pop at idle was there before I replaced all the parts; I was hoping it would be fixed while doing everything else lol. Doesn't look like I'll get to the compression test tonight but hopefully I'll have time tomorrow. I'll also pull the valve cover and have a look. I'm 99% sure the problem is from cyl #4.
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Joined: Apr 2011
Posts: 441
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From: Deep in the heart of Texas
Yeah, isolating which cylinder is the problem will narrow the problem greatly. Mine was popping at idle and almost sounded like I was on the rev limiter at about 5800rpms. Changed plugs, wires, coil, ended up being the ICM. Ran great until the waterpump killed the opti a few weeks later. LOL
Hmm I wondered about the icm. I think that's the only thing I haven't changed lol. I've got about 30 miles on the clutch so just been taking it easy. It hasn't seen 5800 rpm yet.
Last edited by SilverSS07; Feb 15, 2012 at 07:32 PM.
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Didn't get to do compression test today but I pickeep up a thermometer from Lowes and checked the temps on the headers. They are all hot so I'm pretty sure all the cylinders are firing. Hopefully I can do compression test the next day I'm off work.
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Verdad Gallardo Did the compression test today. Highest cyl was 210- lowest was 195. All the plugs looked like they were burning good. I did notice oil all over the rear of the engine and on the bellhousing and trans. From what I've read on here it sounds like the intake gasket is leaking oil at the rear. Could that also cause a vacuum leak making it run like it is?
