not firing at idle but firing once reving ? comp test now done
#1
10K+ Poster!!
Thread Starter
iTrader: (4)
![Default](https://passionford.com/forum/images/icons/icon1.gif)
noticed the r33 sounded very grumpy last night, was missing at idle and misfireing under light load while cold, seemed to drive ok once warm but idle was till very grumpy.
so I started it up this morning and it sounded like a Scooby !
on pulling number 1 coilpack it made no difference at all its not firing at idle at all just on number 1!
i checked all the other cylinders and there all firing, so i swapped number 1 with number 3 coil pack, then spark plug and finally injector, i changed them one at a time and restarted each time and its still not firing on number 1 still.
i also checked number 1 coil with the plug in and i have spark.
the strange thing is if im revving it from around 2000 rpm upwards its firing on number 1 as when i disconnect the coilpack i can hear it go from running perfect and smooth to grumpy as fuck.
im thinking most likely a valve that is open enough to not let it fire at idle, but once the revs increase slightly and the compression isn't escapeing quick enough its still firing.
i will comp test next just thought id put this up incase anyone thinks of something ive missed.
pretty peeved tbh havnt used it much since being set up after manifold sorted, cambelt done and retuned and just done bottom pulley, i may consider an r35 if the engines gotta be pulled and just break it.
so I started it up this morning and it sounded like a Scooby !
on pulling number 1 coilpack it made no difference at all its not firing at idle at all just on number 1!
i checked all the other cylinders and there all firing, so i swapped number 1 with number 3 coil pack, then spark plug and finally injector, i changed them one at a time and restarted each time and its still not firing on number 1 still.
i also checked number 1 coil with the plug in and i have spark.
the strange thing is if im revving it from around 2000 rpm upwards its firing on number 1 as when i disconnect the coilpack i can hear it go from running perfect and smooth to grumpy as fuck.
im thinking most likely a valve that is open enough to not let it fire at idle, but once the revs increase slightly and the compression isn't escapeing quick enough its still firing.
i will comp test next just thought id put this up incase anyone thinks of something ive missed.
pretty peeved tbh havnt used it much since being set up after manifold sorted, cambelt done and retuned and just done bottom pulley, i may consider an r35 if the engines gotta be pulled and just break it.
Last edited by scoooby slayer; 21-01-2014 at 11:50 AM.
#6
10K+ Poster!!
Thread Starter
iTrader: (4)
![Default](https://passionford.com/forum/images/icons/icon1.gif)
still waiting on kit for the capri mate, r33 is my main car though so will need fixing or replaceing asap.
ive just been and got mcdonalds and its now missing constantly, I don't know if its because it progressively getting worse or where ive swapped plugs, coilpacks and injectors around it is bad now though missing and hesitateing all the time
ive just been and got mcdonalds and its now missing constantly, I don't know if its because it progressively getting worse or where ive swapped plugs, coilpacks and injectors around it is bad now though missing and hesitateing all the time
![Sad](https://passionford.com/forum/images/smilies/icon_sad.gif)
Trending Topics
#8
10K+ Poster!!
Thread Starter
iTrader: (4)
![Default](https://passionford.com/forum/images/icons/icon1.gif)
the thing is its not firing at all on cylinder 1, I can pull the lead of the coilpack and it makes no difference, and the plug is sparking fine.
yet all other cylinders are fireing fine.
#10
10K+ Poster!!
Thread Starter
iTrader: (4)
![Default](https://passionford.com/forum/images/icons/icon1.gif)
I have a comp tester and a camera so il have to have a good look asap.
#11
![Default](https://passionford.com/forum/images/icons/icon1.gif)
So again.
Check for a signal to that coil.
Check the injector is firing at that cylinder.
Any non-fire, will result in a lean reading via a lambda sensor, not rich. However if o2 is in closed loop, this false lean condition may then lead to the ecu richening things up, so screwing everything up
Is the plug wet or dry ? How does it look ?
Check for a signal to that coil.
Check the injector is firing at that cylinder.
Any non-fire, will result in a lean reading via a lambda sensor, not rich. However if o2 is in closed loop, this false lean condition may then lead to the ecu richening things up, so screwing everything up
Is the plug wet or dry ? How does it look ?
#12
10K+ Poster!!
Thread Starter
iTrader: (4)
![Default](https://passionford.com/forum/images/icons/icon1.gif)
So again.
Check for a signal to that coil.
Check the injector is firing at that cylinder.
Any non-fire, will result in a lean reading via a lambda sensor, not rich. However if o2 is in closed loop, this false lean condition may then lead to the ecu richening things up, so screwing everything up
Is the plug wet or dry ? How does it look ?
Check for a signal to that coil.
Check the injector is firing at that cylinder.
Any non-fire, will result in a lean reading via a lambda sensor, not rich. However if o2 is in closed loop, this false lean condition may then lead to the ecu richening things up, so screwing everything up
Is the plug wet or dry ? How does it look ?
the plugs I looked at 1 and 3 were dry a little sooty but nothing I didn't expect due to the tune.
the car doesn't run closed loop. it only has the narrowbands on and abbey said there not connected anyway into the fcon. my wideband isn't connected to it just my gauge.
that is the one thing that threw me as I expected plug number 1 to be wet with fuel but it wasn't it was bone dry. so I swapped injectors 1 and 3 thinking the injector might be a little blocked and not flowing at idle but swapping injectors made no difference.
I guess it could be electrical related and the injector isn't being told to open correctly ?
I guess I can check the voltage at the injector and check its the same as a cylinder that's firing at idle.
Last edited by scoooby slayer; 19-01-2014 at 09:34 PM.
#13
PassionFord Post Whore!!
![Default](https://passionford.com/forum/images/icons/icon1.gif)
I've worked on 2 Imprezas that have lost their earths to one injector... Faulty injector loom...
Sounds like wiring to me... Might be worth wiggling the injector loom, or inspecting for damage... Check for multi plugs further back aswell...
Sounds like wiring to me... Might be worth wiggling the injector loom, or inspecting for damage... Check for multi plugs further back aswell...
Last edited by slammedorion; 19-01-2014 at 10:38 PM.
#16
PassionFord Post Whore!!
![Default](https://passionford.com/forum/images/icons/icon1.gif)
My cossie had a problem running problem which turned out to be the pin in the Cts plug had dropped back slightly.
So the wire looked in the plug from the back but didn't actually touch the sensor.
Worth a check.
So the wire looked in the plug from the back but didn't actually touch the sensor.
Worth a check.
#18
![Default](https://passionford.com/forum/images/icons/icon1.gif)
the plugs I looked at 1 and 3 were dry a little sooty but nothing I didn't expect due to the tune.
the car doesn't run closed loop. it only has the narrowbands on and abbey said there not connected anyway into the fcon. my wideband isn't connected to it just my gauge.
that is the one thing that threw me as I expected plug number 1 to be wet with fuel but it wasn't it was bone dry. so I swapped injectors 1 and 3 thinking the injector might be a little blocked and not flowing at idle but swapping injectors made no difference.
I guess it could be electrical related and the injector isn't being told to open correctly ?
I guess I can check the voltage at the injector and check its the same as a cylinder that's firing at idle.
the car doesn't run closed loop. it only has the narrowbands on and abbey said there not connected anyway into the fcon. my wideband isn't connected to it just my gauge.
that is the one thing that threw me as I expected plug number 1 to be wet with fuel but it wasn't it was bone dry. so I swapped injectors 1 and 3 thinking the injector might be a little blocked and not flowing at idle but swapping injectors made no difference.
I guess it could be electrical related and the injector isn't being told to open correctly ?
I guess I can check the voltage at the injector and check its the same as a cylinder that's firing at idle.
if it's bone dry, then it is a sign the injector is not firing, so check for a signal.
Voltage is no use. You either need a meter with pulse width, duty cycle, or better still a scope which will give you a much easier to view picture of any signal.
Well...that does assume there is a 12v supply to the injector plug as well, so in that respect alone yes a volt meter could be used to verify that aspect on it's own.
It could be a mechanical problem, but it would be a strange one.
#19
10K+ Poster!!
Thread Starter
iTrader: (4)
![Default](https://passionford.com/forum/images/icons/icon1.gif)
well things aren't looking good, my comp tester is crap so ive ordered a new one but I got a rough reading and number 1 is 4 bar cranking, number 3 showed 8 bar.
also while cranking with the tester in number 1 there isn't much of a brake in the cranking when it hits compression I can feel and hear its well down but number 4 I know when it fires you can hear and feel it easily trying to stall the starter slightly, I think its defo mechanical failure
if I try the oil in the bore trick and it doesn't bring the comp up at all that will indicate a valve issue wouldn't it ?
also while cranking with the tester in number 1 there isn't much of a brake in the cranking when it hits compression I can feel and hear its well down but number 4 I know when it fires you can hear and feel it easily trying to stall the starter slightly, I think its defo mechanical failure
![Sad](https://passionford.com/forum/images/smilies/icon_sad.gif)
if I try the oil in the bore trick and it doesn't bring the comp up at all that will indicate a valve issue wouldn't it ?
#20
![Default](https://passionford.com/forum/images/icons/icon1.gif)
Carry out compression test with throttle open, even a cheapy gauge works fine. Although even 8 bar doesnt sound very high. Could depend on cam timing and cam profile though.
Generally a low reading will be more indicative of a piston/ring problem ( or HG )
Almost zero would be more like a burnt valve or valve related.
just depends really though.
Of more interest though....exactly what is the history leading to this problem ?
If it is a major mechanical issue, its unlikely it just started doing this at random during normal driving.
So what events led up to the problem ?
Generally a low reading will be more indicative of a piston/ring problem ( or HG )
Almost zero would be more like a burnt valve or valve related.
just depends really though.
Of more interest though....exactly what is the history leading to this problem ?
If it is a major mechanical issue, its unlikely it just started doing this at random during normal driving.
So what events led up to the problem ?
#21
10K+ Poster!!
Thread Starter
iTrader: (4)
![Default](https://passionford.com/forum/images/icons/icon1.gif)
Carry out compression test with throttle open, even a cheapy gauge works fine. Although even 8 bar doesnt sound very high. Could depend on cam timing and cam profile though.
Generally a low reading will be more indicative of a piston/ring problem ( or HG )
Almost zero would be more like a burnt valve or valve related.
just depends really though.
Of more interest though....exactly what is the history leading to this problem ?
If it is a major mechanical issue, its unlikely it just started doing this at random during normal driving.
So what events led up to the problem ?
Generally a low reading will be more indicative of a piston/ring problem ( or HG )
Almost zero would be more like a burnt valve or valve related.
just depends really though.
Of more interest though....exactly what is the history leading to this problem ?
If it is a major mechanical issue, its unlikely it just started doing this at random during normal driving.
So what events led up to the problem ?
the engine has done about 30k from what I can gather, number 2 showed 6 bar and number 1 4 bar im hopeing it might just be headgasket blown between 1 and 2.
im sure she will be down on compression its gotta be due to mileage done, but at 80c oil temp was holding 80 psi oil pressure so im sure the rotating assembly will be in good health, and a refresh and the 1.06 ar housing maybe go for 700 hp.
its not really shown any issues except a little richer at idle and grumpier.
my gauge doesn't hold the value so difficult to see exact reading il do a full check dry then wet once my tester is here.
#22
Too many posts.. I need a life!!
![Default](https://passionford.com/forum/images/icons/icon1.gif)
Out of interest how many miles will a rb26 do at this power level or say 550+hp if its well looked after and treated with respect ect? From what most people say a 400+ cossie engine will normally do 30k odd miles before it starts to get tired, wonderd how the rb26 compares?
#23
10K+ Poster!!
Thread Starter
iTrader: (4)
![Default](https://passionford.com/forum/images/icons/icon1.gif)
Out of interest how many miles will a rb26 do at this power level or say 550+hp if its well looked after and treated with respect ect? From what most people say a 400+ cossie engine will normally do 30k odd miles before it starts to get tired, wonderd how the rb26 compares?
I spoke to abbey about this when they mapped it, its really due now for a refresh.
if the components are ok and its rebuildable the timeframe and cost will be ok and I could go for the 700 hp then
![Grin](https://passionford.com/forum/images/smilies/icon_smile.gif)
all im aware of is the engine was built and stack dash fitted, at 10k miles had headgasket, at 25k miles had gt40 turbo fitted and now upto 30k miles.
il know more once ive comp tested it.
#25
10K+ Poster!!
Thread Starter
iTrader: (4)
![Default](https://passionford.com/forum/images/icons/icon1.gif)
I have comp test results now.
1 50 psi, 2 55 psi, 3 141 psi, 4 143 psi, 5 143 psi, 6 137 psi
so I phoned abbey and said I suspect headgasket blown between 1 and 2, I checked it by putting 50 psi down the plug hole of number 1 on compression stroke and the air blew out of number 2 plug hole lol
its always had a little stutter when cold like an odd random misfire now and then that would always be gone once warmed up until the last time I drove it.
I am sure there has been a tiny leak there for a while that has been sealing up once warm with expansion and has now blown through.
so abbey are now quoteing me for a headgasket job, being as the oil pressure is holding over 5 bar hot and the 3 - 6 comp test results are good im gonna just run the engine some more, it cant be that tired it made 560 atw less than 1k miles ago.
the only decision I have now is if I should replace the 0.84 ar housing with the 1.06ar housing which I have here ready to go, it is mental responsive and when I try and run 1 bar of boost it creeps upto 1.3 bar by 8000 rpm indicating to me the housing is so restrictive that even with a 60 mm gate fully open it still cant maintain 1 bar.
even at 30k its not massive mileage and I dare bet a lot of that was pottering about not like the fairly constant abuse I give it lol
with the less restrictive housing im hopeful it may hit 600 atw
1 50 psi, 2 55 psi, 3 141 psi, 4 143 psi, 5 143 psi, 6 137 psi
so I phoned abbey and said I suspect headgasket blown between 1 and 2, I checked it by putting 50 psi down the plug hole of number 1 on compression stroke and the air blew out of number 2 plug hole lol
its always had a little stutter when cold like an odd random misfire now and then that would always be gone once warmed up until the last time I drove it.
I am sure there has been a tiny leak there for a while that has been sealing up once warm with expansion and has now blown through.
so abbey are now quoteing me for a headgasket job, being as the oil pressure is holding over 5 bar hot and the 3 - 6 comp test results are good im gonna just run the engine some more, it cant be that tired it made 560 atw less than 1k miles ago.
the only decision I have now is if I should replace the 0.84 ar housing with the 1.06ar housing which I have here ready to go, it is mental responsive and when I try and run 1 bar of boost it creeps upto 1.3 bar by 8000 rpm indicating to me the housing is so restrictive that even with a 60 mm gate fully open it still cant maintain 1 bar.
even at 30k its not massive mileage and I dare bet a lot of that was pottering about not like the fairly constant abuse I give it lol
with the less restrictive housing im hopeful it may hit 600 atw
![Grin](https://passionford.com/forum/images/smilies/icon_smile.gif)
Last edited by scoooby slayer; 21-01-2014 at 11:57 AM.
#26
![Default](https://passionford.com/forum/images/icons/icon1.gif)
How is the gate plumbed ? And can you confirm it is fully open ?
The same turbo on a friends 2.35 engine...even after changing from the 0.95 to the small 0.85 housing, we had more issues trying to make boost, nevermind making too much ! lol
It was a lethargic bastard.
At least a HG isnt a major issue, dont be driving it though til its fixed in case it damages the head
The same turbo on a friends 2.35 engine...even after changing from the 0.95 to the small 0.85 housing, we had more issues trying to make boost, nevermind making too much ! lol
It was a lethargic bastard.
At least a HG isnt a major issue, dont be driving it though til its fixed in case it damages the head
#27
10K+ Poster!!
Thread Starter
iTrader: (4)
![Default](https://passionford.com/forum/images/icons/icon1.gif)
How is the gate plumbed ? And can you confirm it is fully open ?
The same turbo on a friends 2.35 engine...even after changing from the 0.95 to the small 0.85 housing, we had more issues trying to make boost, nevermind making too much ! lol
It was a lethargic bastard.
At least a HG isnt a major issue, dont be driving it though til its fixed in case it damages the head
The same turbo on a friends 2.35 engine...even after changing from the 0.95 to the small 0.85 housing, we had more issues trying to make boost, nevermind making too much ! lol
It was a lethargic bastard.
At least a HG isnt a major issue, dont be driving it though til its fixed in case it damages the head
at 1 bar the boost controller cant hold it and it creeps to 1.3 bar and the screamer is screaming its tits off lol
if the gate wasn't opening properly as I run more boost the problem would get worse as Id need to vent more not less so I don't think theres any problems with the boost control.
strange that on the 2.35 my 2.7 is the complete opposite of lethargic, in top gear I can get 0.5 bar by 3500 rpm and full boost in before 4500 rpm.
I was worried about it and that's why I didn't fit the 1.06 ar as I thought it would be to laggy but it threw me because the car wasn't right when I bought it.
at 1.7 bar it comes in hard and fast but it cant maintain it and it drops off to 1.5 bar up the top which im sure is down to the housing being so small its restricting the engine, from the feel of the car response wise I know I need to move that curve upwards.
since ive fixed all the leaks on the inlet side and the hot side the response is very good, but I don't like having an engine brake on there which is what I think ive got.
ive certainly got enough response that I can afford to loose some hopefully in trade for some more top end power and a healthier less restricted engine.
if I could monitor the back pressure im sure it would be bad.
I have been told that these twin scroll housings need sizeing 1 size down to match an open scroll, making my 0.84 the equivelant of a 0.63 which is what I ran on my yb engines at 450 - 500 hp, but im now looking at 650 - 700 hp hopefully.
Last edited by scoooby slayer; 21-01-2014 at 03:22 PM.
#28
10K+ Poster!!
Thread Starter
iTrader: (4)
![Default](https://passionford.com/forum/images/icons/icon1.gif)
ive been reading up on the housings and my 0.84 will flow 32 lb/min of air flat out, now im maxing out at 640 hp so 20 hp per lb of flow.
the 1.06 housing flows 35 lb/min flat out so should in theory allow upto 700 hp of flow, at least if I change it and use the corrected figures at cell temp on abbeys dyno I will have some comparable results to check my theory
the 1.06 housing flows 35 lb/min flat out so should in theory allow upto 700 hp of flow, at least if I change it and use the corrected figures at cell temp on abbeys dyno I will have some comparable results to check my theory
![Grin](https://passionford.com/forum/images/smilies/icon_smile.gif)
#32
10K+ Poster!!
Thread Starter
iTrader: (4)
![Default](https://passionford.com/forum/images/icons/icon1.gif)
heres the boost plot steve
![Name: M40BHP_2_zps35ea73ee.jpg
Views: 32
Size: 221.7 KB](https://passionford.com/forum/attachments/general-car-related-discussion/69710d1501451052-not-firing-at-idle-but-firing-once-reving-comp-test-now-done-m40bhp_2_zps35ea73ee.jpg)
and it indicates what it does on the road as ive seen 0.5 bar at 3500 rpm and full boost by 4300 rpm, im happy to loose 500 rpm of that if it gives me a less restrictive turbo that will reduce backpressure in the engine and should hopefully make abit more power at the same boost.
the boost actually only drops of to 1.6 bar not 1.5, when I watch my in car gauge though I have seen 1.9 bar here and there, ive been informed aswell by a very reliable source that the 0.84 housing chokes the turbo so much that I may aswell just have a gt4088 instead.
![Name: M40BHP_2_zps35ea73ee.jpg
Views: 32
Size: 221.7 KB](https://passionford.com/forum/attachments/general-car-related-discussion/69710d1501451052-not-firing-at-idle-but-firing-once-reving-comp-test-now-done-m40bhp_2_zps35ea73ee.jpg)
and it indicates what it does on the road as ive seen 0.5 bar at 3500 rpm and full boost by 4300 rpm, im happy to loose 500 rpm of that if it gives me a less restrictive turbo that will reduce backpressure in the engine and should hopefully make abit more power at the same boost.
the boost actually only drops of to 1.6 bar not 1.5, when I watch my in car gauge though I have seen 1.9 bar here and there, ive been informed aswell by a very reliable source that the 0.84 housing chokes the turbo so much that I may aswell just have a gt4088 instead.
Thread
Thread Starter
Forum
Replies
Last Post
TPM961
Restorations, Rebuilds & Projects.
19
15-01-2018 10:50 AM