problems - high idle, jittery at low revs, popping, whistling noise
10-11-07, 07:28 PM
#1
Full Member
Thread Starter
problems - high idle, jittery at low revs, popping, whistling noise
Hi all,
firstly -
car: 1996 Series 7 RB Bathurst, jap import to NZ
kms: 85000kms, 44000miles (i think about 44)
modifications: HKS super dragger catback, turbo timer, greddy boost gauge + headunit/amp/sub
problems that have appeared in the last 5000kms:
- Car is idling between 1500 and 2000rpm, my tach is slightly iffy and sometimes reads 1000rpm higher, but this only seems to be at cruising speeds so i feel it is accurate 'enough' at idle. The idle adjust screw does not make the idle any lower, only higher if you turn it up. dashpot seems ok, there is slack in the throttle cable also and i have cleaned the TB where I can.
- popping at idle where it did not 5000kms ago, sort of in between popping and backfiring - possibly the 02 sensor? When it pops, the car shakes slightly with each pop, but not violently - could this be a product of worn motor mounts?
- boost gauge reads 500mmHg at idle. I have nfi how to read/convert mmHg to anything else so I don't know if this is the right level of vacuum or not at idle. I cant see any vac leaks immediatly after checking the basic ones such as map sensor and boost gauge/bov/recirc valve lines etc. I have not taken the UIM off to check under there yet though.
- very jerky to drive at slight throttle/sudden changes in throttle, makes parking lots a bitch. I think this might be a by product of the high idle however. I have checked the TPS for voltages and it is within spec as per the FD3S.net site.
- seems 'flat' at times when accelerating - to avoid damage I have not been boosting it much since these issues have started but it doesnt seem to boost as easily as it did before - possibly a clogged Cat? The plastic tubing for the intercooler pipes and elbow are on tight so i dont think its a boost leak, but I could be wrong.
- whistling/slight squeeling noise coming from front of the engine, this just started in the last few days so i dont think its related. Could possibly be a belt or a bearing for a pulley on the way out? Increases in speed with revs and is constant at idle/cruising. There is too much wind/engine noise to tell if it continues with high revs but i suspect it does.
If anyone has any ideas on what I might like to look at to resolve these issues, it would be greatly appreciated. I have had a search and tryed a few things (replacing grounds, replacing sparkplugs, checking TPS) but before i continue i would like to get an idea on what to look at so i am not aimlessly poking and prodding at things - especially if it involves downtime for the car (removing UIM and doing all the vac lines for example).
Many thanks in advance.
Also: at your request I can supply video/photos and can pull codes from the ECU which I have not done yet.
firstly -
car: 1996 Series 7 RB Bathurst, jap import to NZ
kms: 85000kms, 44000miles (i think about 44)
modifications: HKS super dragger catback, turbo timer, greddy boost gauge + headunit/amp/sub
problems that have appeared in the last 5000kms:
- Car is idling between 1500 and 2000rpm, my tach is slightly iffy and sometimes reads 1000rpm higher, but this only seems to be at cruising speeds so i feel it is accurate 'enough' at idle. The idle adjust screw does not make the idle any lower, only higher if you turn it up. dashpot seems ok, there is slack in the throttle cable also and i have cleaned the TB where I can.
- popping at idle where it did not 5000kms ago, sort of in between popping and backfiring - possibly the 02 sensor? When it pops, the car shakes slightly with each pop, but not violently - could this be a product of worn motor mounts?
- boost gauge reads 500mmHg at idle. I have nfi how to read/convert mmHg to anything else so I don't know if this is the right level of vacuum or not at idle. I cant see any vac leaks immediatly after checking the basic ones such as map sensor and boost gauge/bov/recirc valve lines etc. I have not taken the UIM off to check under there yet though.
- very jerky to drive at slight throttle/sudden changes in throttle, makes parking lots a bitch. I think this might be a by product of the high idle however. I have checked the TPS for voltages and it is within spec as per the FD3S.net site.
- seems 'flat' at times when accelerating - to avoid damage I have not been boosting it much since these issues have started but it doesnt seem to boost as easily as it did before - possibly a clogged Cat? The plastic tubing for the intercooler pipes and elbow are on tight so i dont think its a boost leak, but I could be wrong.
- whistling/slight squeeling noise coming from front of the engine, this just started in the last few days so i dont think its related. Could possibly be a belt or a bearing for a pulley on the way out? Increases in speed with revs and is constant at idle/cruising. There is too much wind/engine noise to tell if it continues with high revs but i suspect it does.
If anyone has any ideas on what I might like to look at to resolve these issues, it would be greatly appreciated. I have had a search and tryed a few things (replacing grounds, replacing sparkplugs, checking TPS) but before i continue i would like to get an idea on what to look at so i am not aimlessly poking and prodding at things - especially if it involves downtime for the car (removing UIM and doing all the vac lines for example).
Many thanks in advance.
Also: at your request I can supply video/photos and can pull codes from the ECU which I have not done yet.
10-12-07, 06:45 AM
#3
Senior Member
Hey man seems like you have a few things wrong with it, have you done a compression test?? Are you running a standard ecu?
I had a power FC in my old 7 and swapped it over with my chipped ECU then it did nothing but cough spit and fart down the road so I chucked the PFC back in. I was trying to resolve some issues. What are your vacuum lines like because if they are brittle than you might want to look at replacing them as they tend to leak/break heaps but the series 7's luckily have less of them than the series 6's.
Im having trouble with my car at the mo but different to your problems. I guess start with a compression test and maybe contact someone with another series 7 to swap ecu's over just to see. Do you know any of the FD kai boys in welly? They are a great help especially Steve Metcalf. He helped me so much, hell of a nice guy and always willing to help a guy out.
Let me know how you get on.
I had a power FC in my old 7 and swapped it over with my chipped ECU then it did nothing but cough spit and fart down the road so I chucked the PFC back in. I was trying to resolve some issues. What are your vacuum lines like because if they are brittle than you might want to look at replacing them as they tend to leak/break heaps but the series 7's luckily have less of them than the series 6's.
Im having trouble with my car at the mo but different to your problems. I guess start with a compression test and maybe contact someone with another series 7 to swap ecu's over just to see. Do you know any of the FD kai boys in welly? They are a great help especially Steve Metcalf. He helped me so much, hell of a nice guy and always willing to help a guy out.
Let me know how you get on.
10-12-07, 07:36 PM
#4
Full Member
Thread Starter
hey mate, where in NZ are you? always good to see other kiwis on this board!
i havnt done a compression test, I think comp is good though since it has no problems starting and its never flooded, its very reliable as far as these cars go.
i dont know of any of the FD Kai guys, I was considering calling steve harding and see if he could have a look or maybe try get hold of the lawton guys since they are close to where i live (paekok hill)
anyway, my car is a white series 7 with no wing and the #plate 'pie' so if you happen to see me around holla up :p
i havnt done a compression test, I think comp is good though since it has no problems starting and its never flooded, its very reliable as far as these cars go.
i dont know of any of the FD Kai guys, I was considering calling steve harding and see if he could have a look or maybe try get hold of the lawton guys since they are close to where i live (paekok hill)
anyway, my car is a white series 7 with no wing and the #plate 'pie' so if you happen to see me around holla up :p
10-12-07, 10:09 PM
#5
Senior Member
I would try ringing Graham from Zion motors in pram, hes a nice guy and knows his stuff on rotors. I had my s4 engine built by him years ago, never missed a beat the whole time I owned it and I thrashed the living pants off it for 3 more years! You may remember my old Purple series 6 from pram with the plate BADSVN, was one of the fastest cars around until I got the engine rebuilt then it just never ran right again. Cheers M's racing for cocking up yet another batty!
Anyway I will try and get Steves number for you as he may be keen to help, otherwise ring graham from Zion Motors.
Oh and I live in Auckland now so prob not much chance in seeing me around lol.
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