Poor running - advice welcome.
Discussion
I thought I'd start a new thread as my problems seem to be changing.
Long story is I bought my 4.5 and treated it to a major 12k service with a well known independent. They did all the normal 12k service and in addition replaced the throttle pots. The set the car up as best they could but it was still not running perfectly in my opinion. I did a track day with UKkid35 and we both felt the car could give more. The remaining problem was cracked manifold which I had replaced with ACT performance items.
In fitting the ACT manifolds both lambdas co-incidentally seemed to die. I had it back to the indy who fitted exhaust gaskets to stop any leaks and reset the adaptives amd returned the car 'running a lot better' but it had developed a high idle (circa 1050 - 1100 RPM) The replaced a drilled bolt in the #6 and #8 intakes but still could not get it to idle perfectly. They advised possibly looking at rebuilding the intake if I couldn't live with it.
After this I took the car for a 300 mile drive. The performance was bad. It was worse than before the ACT manifolds were fitted. It developed a missfire under load and the throttle response was off. It was like the car would bog down if you gave it too much gas. I remember the revs wouldn't drop readily. It was like the throttle was sticking and the car would almost drive itself.
I wanted to try and fix this myself as spending lots of cash is not getting me very far with garages. I'm sure they will get it running 100% eventually but I'd rather learn myself.
I've since now replaced all coils and HT leads. In stripping the intake apart I found that the drivers side airbox was badly split at the bottom. There was about a 6 inch gap along the bottom of the airbox. I've done a good repair with mastik and self tappers and it's now airtight.
In fitting the coilpacks accidentally the even (rearward) is pointing the wrong direction. However in order to save the skin on my hands I've swapped the HT leads over and the car now starts and idles ok.
So.. I thought I had it nailed. I was going to take the car for a test drive and pulled away and it felt sluggish. My house is at the bottom of a very short but very steep hill. It's gravelly and I have to use momentum to carry me up as traction is limited.
As the car was sluggish the revs and power seemed to drop away and the car stalled. To make matters worse the lane is lined by cotswold stone walls. After climbing out the passenger side I managed to finally reverse the car back down to my driveway. I was hoping it was something simple like a brake binding but I think it's engine related.
I've plugged into the ECU and went to look if I could see anything. I reset the adaptive and ran the car for a bit.
The good news is the idle is better under control. It's now idling at 750RPM which is a bit low.
At idle adaptive one is 22.7 and spiking to 27.3 in a loop. Adaptive two is around 24.
Both lambdas are reporting ok. I'm not getting any faults.
I'm wondering where to go next. I've replaced a lot but was really hoping the coils and leads would get the car running well. The engine note sounds quite different which I'm attributing to the airbox being repaired.
I'm not really sure what I should be seeing in the ECU software to be honest.
Any advice is welcome
Long story is I bought my 4.5 and treated it to a major 12k service with a well known independent. They did all the normal 12k service and in addition replaced the throttle pots. The set the car up as best they could but it was still not running perfectly in my opinion. I did a track day with UKkid35 and we both felt the car could give more. The remaining problem was cracked manifold which I had replaced with ACT performance items.
In fitting the ACT manifolds both lambdas co-incidentally seemed to die. I had it back to the indy who fitted exhaust gaskets to stop any leaks and reset the adaptives amd returned the car 'running a lot better' but it had developed a high idle (circa 1050 - 1100 RPM) The replaced a drilled bolt in the #6 and #8 intakes but still could not get it to idle perfectly. They advised possibly looking at rebuilding the intake if I couldn't live with it.
After this I took the car for a 300 mile drive. The performance was bad. It was worse than before the ACT manifolds were fitted. It developed a missfire under load and the throttle response was off. It was like the car would bog down if you gave it too much gas. I remember the revs wouldn't drop readily. It was like the throttle was sticking and the car would almost drive itself.
I wanted to try and fix this myself as spending lots of cash is not getting me very far with garages. I'm sure they will get it running 100% eventually but I'd rather learn myself.
I've since now replaced all coils and HT leads. In stripping the intake apart I found that the drivers side airbox was badly split at the bottom. There was about a 6 inch gap along the bottom of the airbox. I've done a good repair with mastik and self tappers and it's now airtight.
In fitting the coilpacks accidentally the even (rearward) is pointing the wrong direction. However in order to save the skin on my hands I've swapped the HT leads over and the car now starts and idles ok.
So.. I thought I had it nailed. I was going to take the car for a test drive and pulled away and it felt sluggish. My house is at the bottom of a very short but very steep hill. It's gravelly and I have to use momentum to carry me up as traction is limited.
As the car was sluggish the revs and power seemed to drop away and the car stalled. To make matters worse the lane is lined by cotswold stone walls. After climbing out the passenger side I managed to finally reverse the car back down to my driveway. I was hoping it was something simple like a brake binding but I think it's engine related.
I've plugged into the ECU and went to look if I could see anything. I reset the adaptive and ran the car for a bit.
The good news is the idle is better under control. It's now idling at 750RPM which is a bit low.
At idle adaptive one is 22.7 and spiking to 27.3 in a loop. Adaptive two is around 24.
Both lambdas are reporting ok. I'm not getting any faults.
I'm wondering where to go next. I've replaced a lot but was really hoping the coils and leads would get the car running well. The engine note sounds quite different which I'm attributing to the airbox being repaired.
I'm not really sure what I should be seeing in the ECU software to be honest.
Any advice is welcome
Edited by Rawhide on Monday 23 January 23:24
Hi Neil, the airbox really scares me. There was a recent case on here of an engine self destructing when a nut or bolt got in to a cylinder. I would check your self tappers to make absolutely sure that there's no way they could come lose. The crank case breather fixings are another potential danger point. I really think the 4.5 airbox is a piece of junk.
Edited by ukkid35 on Tuesday 24th January 08:17
If the adaptive is that high at idle then the pots need setting up and I agree you need to get the idle rpms up. You can have a go at setting things up yourself, but I find I never can do as good a job as a TVR specialist - I just don't get as much practice.
Edited by Steve_T on Tuesday 24th January 08:20
Sounds like good progress being made - the adaptives are far too high ATM - they want to be from -10 to 0 I think (at least they do on a 4.2) - you are running very rich there which would make it sluggish.
Lambdas will die when fitting acts - mine did - as they HATE silicon and you use loads to glue the sections together - its just a pain.
Sorting the leak in the air of would likely reduce the amount of oxygen hittin the chambers. If it was setup based on that then you'd expect it to overfuel now, as it is. It's weird the other bank is so far off though.
If take link bar off and start from scratch on the setup. I'm not sure what you did with the coilpacks, but I'd be tempted to just put it on the right way - it probably makes no difference but id remove that potential gotcha too.
Stu
Lambdas will die when fitting acts - mine did - as they HATE silicon and you use loads to glue the sections together - its just a pain.
Sorting the leak in the air of would likely reduce the amount of oxygen hittin the chambers. If it was setup based on that then you'd expect it to overfuel now, as it is. It's weird the other bank is so far off though.
If take link bar off and start from scratch on the setup. I'm not sure what you did with the coilpacks, but I'd be tempted to just put it on the right way - it probably makes no difference but id remove that potential gotcha too.
Stu
ukkid35 said:
Hi Neil, the airbox really scares me. There was a recent case on here of an engine self destructing when a nut or bolt got in to a cylinder. I would check your self tappers to make absolutely sure that there's no way they could come lose. The crank case breather fixings are another potential danger point. I really think the 4.5 airbox is a piece of junk.
Hey Paul, I know. I relocated one redundant one from the top and used it to pull the base together. I used some really strong mastic and it's now really tight. I used mastik on the screw as well.Edited by ukkid35 on Tuesday 24th January 08:17
The crank case breather all looks ok and strong enough.
I agree, it's very shoddy design.
Start from the beginning i say. thats what i had to do to get my idle set, and had similar symptoms of no power and stalling.
Do you have a flow meter? get every cylinder running as close to the required as possible. I set my idle up using a set of feeler gauges to set the butterfly to the same gap, before setting the idle speeds. Got mine idling at 900 cold and 1000 hot and starts with no throttle input.
use the manual and you'll get it. Its frustrating i know as it was for me but got it in the end.
Do you have a flow meter? get every cylinder running as close to the required as possible. I set my idle up using a set of feeler gauges to set the butterfly to the same gap, before setting the idle speeds. Got mine idling at 900 cold and 1000 hot and starts with no throttle input.
use the manual and you'll get it. Its frustrating i know as it was for me but got it in the end.
pmessling said:
Start from the beginning i say. thats what i had to do to get my idle set, and had similar symptoms of no power and stalling.
Do you have a flow meter? get every cylinder running as close to the required as possible. I set my idle up using a set of feeler gauges to set the butterfly to the same gap, before setting the idle speeds. Got mine idling at 900 cold and 1000 hot and starts with no throttle input.
use the manual and you'll get it. Its frustrating i know as it was for me but got it in the end.
Hi, I don't have a flow meter. I assume this is what the manual describes as ,air synchrometer' The purpose being I assume to measure any differences in butterfly openings from one bank to the other.Do you have a flow meter? get every cylinder running as close to the required as possible. I set my idle up using a set of feeler gauges to set the butterfly to the same gap, before setting the idle speeds. Got mine idling at 900 cold and 1000 hot and starts with no throttle input.
use the manual and you'll get it. Its frustrating i know as it was for me but got it in the end.
What should I be searching for on ebay? air synchrometer does not produce any results.
Did you use the feeler guages instead of the flow meter?
Thanks again..
http://www.ebay.co.uk/itm/CARBURETTOR-SYNCHROMETER...
Search using synchrometer
I used both, feeler gauges to gauge the butterfly gaps and the synchrometer when the engine was running.
Search using synchrometer
I used both, feeler gauges to gauge the butterfly gaps and the synchrometer when the engine was running.
Well, I've spend some time today trying to get it setup.
I first swapped the coil around to remove the from the equation. I then started to setup the throttle pots as per the manual.
I managed to get them balanced but when bringing up the idle they would come out of balance a bit. After lots of fiddling I managed to get them at around 19. The car started but I needed the idle raising a bit.
To cut to the chase I have the car running and it's making power. However it's still pretty lumpy and running rich (popping and smells of fuel) I managed to get it to idle around 1000rpm but more by luck than skill.
I tried adjusting the throttle pots a bit as advised by the manual. I set them both to 18 (not running) and the car started an idles quite smoothly. Any lower and the car seems to want to stall.
I am also getting AFR faults on both banks.
I think where I am going wrong is the butterflys look a touch more more open on the odd bank than the even. Also I think the adpatives are too high still. Any ideas on how to get them down?
I first swapped the coil around to remove the from the equation. I then started to setup the throttle pots as per the manual.
I managed to get them balanced but when bringing up the idle they would come out of balance a bit. After lots of fiddling I managed to get them at around 19. The car started but I needed the idle raising a bit.
To cut to the chase I have the car running and it's making power. However it's still pretty lumpy and running rich (popping and smells of fuel) I managed to get it to idle around 1000rpm but more by luck than skill.
I tried adjusting the throttle pots a bit as advised by the manual. I set them both to 18 (not running) and the car started an idles quite smoothly. Any lower and the car seems to want to stall.
I am also getting AFR faults on both banks.
I think where I am going wrong is the butterflys look a touch more more open on the odd bank than the even. Also I think the adpatives are too high still. Any ideas on how to get them down?
Edited by Rawhide on Saturday 28th January 16:55
You need to use a air synchometer on the throttles whilst idling to set both sides to what the manual says by adjusting the throttle linkage bar. think the manuals say between 4.5-5.
I too had the bad AFR, and spent ages setting it all up.
I went to the extreme as to removing the throttle bodies and replacing the orings, i did find several loose bolts that held them down as i had it where i would set the throttle up, go for a drive and the idle would get higher and higher to around 1600 rpm idle which is not good.
I too had the bad AFR, and spent ages setting it all up.
I went to the extreme as to removing the throttle bodies and replacing the orings, i did find several loose bolts that held them down as i had it where i would set the throttle up, go for a drive and the idle would get higher and higher to around 1600 rpm idle which is not good.
pmessling said:
You need to use a air synchometer on the throttles whilst idling to set both sides to what the manual says by adjusting the throttle linkage bar. think the manuals say between 4.5-5.
I too had the bad AFR, and spent ages setting it all up.
I went to the extreme as to removing the throttle bodies and replacing the orings, i did find several loose bolts that held them down as i had it where i would set the throttle up, go for a drive and the idle would get higher and higher to around 1600 rpm idle which is not good.
I've been using the syncrometer but the manual says (summarised)I too had the bad AFR, and spent ages setting it all up.
I went to the extreme as to removing the throttle bodies and replacing the orings, i did find several loose bolts that held them down as i had it where i would set the throttle up, go for a drive and the idle would get higher and higher to around 1600 rpm idle which is not good.
1)Remove Bar
2) Shut butterflys (which I'm doing by winding of the idle screw)
3) adjust throttle pots to 14.8
4) Refit bar and tighten up ensuring balance (bloody hard!)
5) adjust idle screw to set pots to 19 (I managed 19.8 but for both pots)
6) Block purge line and start engine (have done but without blocking purge line, having trouble identifying it)
7) adjust bar to ensure banks are between 4 & 5
Can anyone describe the purge line as the manual is for a 4.2 and the picture is not clear to me. How important is this?
Edited by Rawhide on Saturday 28th January 20:26
I've managed to get all the cylinders balanced with the syncrometer. They are all around 5 now as per the manual. After adjusting the throttle pots with the engine running and resetting the maps I've managed to get negative adaptive setting and the AFR faults have cleared.
So it's looking better but the idle is now too high. Its around 12/1300 at idle.
I am thinking there is a secondary fault here and I might need to remove the intake.
So it's looking better but the idle is now too high. Its around 12/1300 at idle.
I am thinking there is a secondary fault here and I might need to remove the intake.
If everything is now balanced, try winding off the idle screw reducing the idle. I think the readings for the throttle pots are more a guide, as even after setting mine then setting the idle the TP readings where lower. Mine idles about 900 cold, and 1000 warm, but starts with no throttle.
Just try adjusting the idle half a turn at a time. and see how that goes.
Just try adjusting the idle half a turn at a time. and see how that goes.
Rawhide said:
an anyone describe the purge line as the manual is for a 4.2 and the picture is not clear to me. How important is this?
It is the small of the two lines going into the oil catch tank on the underside of the drivers side airbox. It does need to be blocked as per the manual as it will let air bypass the throttles if you just disconnect it.Edited by Tanguero on Saturday 28th January 21:31
Many thanks guys. Really appreciated. I've learned a lot today as it's the first time I've tackled anything like this on a car. Dirt bikes are much easier.
I've also lost the retaining clip for the bar which has really pissed me off I was working on a gravel driveway and there is no sign of it. Something to order on monday
I've also lost the retaining clip for the bar which has really pissed me off
I was working on a gravel driveway and there is no sign of it. Something to order on monday Gassing Station | Cerbera | Top of Page | What's New | My Stuff