Idle Wierdness - Missing A Beat

[turbs33]

Hey all,

Just posting this up to see if other may have experienced and recified the same issue with there r33 gtst's.

Car idles nicely at the correct rpm (650rpm from memory). about every 30-45 secods or so its like the motor has a small miss , i feel the engine lightly jolt and revs must drop (happens so quick u dont notice it on the tacho).. This has been happening for some time now, but its getting annoying so i want to try and fix it.

I have new plugs bcpr6es, fuel pump has been replace with a new item, AFM has been cleaned with electrical cleaner.

I have not cleaned aac valve (idle control valve) or replaced the fuel filter.

Any idea what might be causing this.. Coils are good and hold up good under boost and whilst driving the car the problem is not there.. only at idle.

mods include fmic, zorst, std ecu.

[Fixxxer]

A lot of guys running the BCPR6ES plugs at 0.8mm gap find a slight miss at idle.

Mine is running this setup and has a random slight miss at idle sometimes, no problems anywhere else in the rev range.

Don't worry yourself over it.

Fixxxer

[turbs33]

lol cheers for the reply man. its annoying to say the least but if its just the plugs then I could live with that. prior to this i run bpr6es (not bcpr6es) and did not have the problem.. Whats the 'c' in bcpr6es mean ?

[Fixxxer]

C is just the hex size, 5/8 inch. Same plug type though.

Fixxxer

Edited June 21, 2008 by Fixxxer

[turbs33]

cheers mate, always felt the plug without the C (larger body) fit inside the coil packs alot tighter..

Thanks

[Rekin]

I have a similar issue in my r32. Does the miss always happen on idle? Or does it come along a couple of days etc?

Ive noticed that when my battery voltage drops below 13v on idle, the car starts to have the little shakes.

In my case, i believe its the alternator not charging the battery on idle and causing it to drop to 12.5v~.

As the voltage is low, this would cause the injectors, coilpacks to act funny causing a slight vibration etc.

Go to an auto electrican to check your alternator/battery to see if they are running okay.

Doesnt hurt to try as they are happy to check for free.

Let us know on the progress.

[turbs33]

Thanks for the idea Rekin on the alternator voltage at idle. Ill check it out and post up results..

[iseekool]

I have a similar issue in my r32. Does the miss always happen on idle? Or does it come along a couple of days etc?

Ive noticed that when my battery voltage drops below 13v on idle, the car starts to have the little shakes.

In my case, i believe its the alternator not charging the battery on idle and causing it to drop to 12.5v~.

As the voltage is low, this would cause the injectors, coilpacks to act funny causing a slight vibration etc.

Go to an auto electrican to check your alternator/battery to see if they are running okay.

Doesnt hurt to try as they are happy to check for free.

Let us know on the progress.

In addition to this, ensure your battery terminals are clean and ensure there is sufficient grounding. Also check you vacum hoses for fine cracks as a small vacum leak could also show such problems.

Cheers

[frozenwaffles]

yeah i have this too...

[slaughter]

Exact same problem, cleaned afm to no avail, doing full service this weekend including AAC valve will let yous know how i go.

[turbs33]

be interested to know if cleaning the aac valve fixes the issue, or if it is indeed caused by the plugs or low voltage

[Dan_AE86]

sorry to hijack your thread but mine also does similar if not the same thing.

when i pull up to my driveway it idles low and makes a beep/whine while it is idling low then stops when the rpm go up.

Anyone had this/heard to this??

CAR: R33 S1 Stock bar: Catback, k+n panel.

Dan.

[antonirabic]

hey i got a series I gts-t and does the same thing its all good man nothing to stress over i had a heart attach when i got it but meh its fine doesnt do n e thing bad so im not stressed but ye ive noticed it a few times esp at lights

[slaughter]

well buggor34 service my car for me (thanks mate) this included new oil 4100, oil filter, fuel filter, new plugs and also cleaned the AAC and FIXED no more missing im so happy, sorry i couldnt be more helpful in diagnosing but one of the above fixed me problem, we are thinking it was most likely the plugs to be honest as the others were totally screwed that or AAC which wasnt really dirty at all.

[turbs33]

Nice, so fixed for you..

[Fungus Mungus]

i've been having a similar problem for a while now. it always goes away when i put new plugs in, but comes back after a couple hundred kays. never paid too much attention to it until this week.

i had my 100,000km service recently. the only thing not replaced was the plugs (at my request, had NGK iridiums only about 1200km old). the misfire got really bad after a timing problem was fixed. replaced the plugs to be on the safe side and the misfire stopped. the thing is, i'm now experiencing a severe lack in power.

when i say severe, don't just pass it off as a non turbo thing, i'm talking 12-13 seconds to get up to 100km/h pulling onto the freeway. when i put my foot down in any gear after 2nd all it does is make noise. and what a noise. my car has always been legal in the volume department, but this morning i couldn't hear the harley sitting next to me at the lights.

something is very very wrong.

any thoughts? i'm taking it back to the shop that did the service as soon as i get a chance, but work is busy and these guys take a ridiculous amount of time to get anything done. for my major service i was without a car for TWO WEEKS.

any thoughts?