How to set up engine properly?
Discussion
The MIL light was flickering off and on so installed the diagnostic software. Tangeuro helped me there.
So, looking at the data, the oxygen sensors were bad, one dead completely and one very slow. The engine lacked power and travelling at 50mph in 4th and floor it, no response but drop into 3rd and off she goes.
Replaced both sensors which took forever as I have an ACT stainless system fitted. Started her up and now she wouldn't idle. Both throttle pots were within 1% at 19.8 and they indicate smoothly all the way up. So, adjusted the throttle stop screw to keep it idling and that seemed to do it.
Cleared the fault codes, cleared the adaptions both ok, then tried to reset the throttle but it said could not make minimum.
Live data shows the odd bank adaptions around -7%. The even bank goes up to around 25% (limit is 20%) so the MIL light is back on and off as this figure goes out of range. The odd lambda sensor is switching well. The even one goes lean and stays there at 0.1v. Rev it and it starts to switch until it idles again. Checked for air leaks on the manifold and exhaust.
The odd bank injector opening time is 2.7m/s and the evens 3.2m/s.
Have tried several throttle pots in various set ups and no different. Fitted 2 new coils as the spark time on 2 cylinders was way too high and this was cured. New plugs too and checked the leads using a spark tester tool and they are all good.
Tried setting the throttles closed by disconnecting the bar then fitting it so neither moved. Set the pots to 15% as per the software. Start up and she wont idle so adjust the stop again. Now will only idle at around 1,100 rpm and there is a lot more popping in the exhaust. Pots both read 19% at idle and go up together within 2% all the way.
Adaptions are now +4% odds, +26 evens.
So, after 4 hours to fit the sensors and another 4 trying to set the car up, can anyone help with:
1. a sequence of how to set the throttles from the beginning?
2. any ideas as to why the even bank adaptions are way out? (I've reset them after each adjustment along with the fault codes which is always AFR2468)?
3. why the throttle adaption cannot reach minimum?
Any help much appreciated. Thanks.
So, looking at the data, the oxygen sensors were bad, one dead completely and one very slow. The engine lacked power and travelling at 50mph in 4th and floor it, no response but drop into 3rd and off she goes.
Replaced both sensors which took forever as I have an ACT stainless system fitted. Started her up and now she wouldn't idle. Both throttle pots were within 1% at 19.8 and they indicate smoothly all the way up. So, adjusted the throttle stop screw to keep it idling and that seemed to do it.
Cleared the fault codes, cleared the adaptions both ok, then tried to reset the throttle but it said could not make minimum.
Live data shows the odd bank adaptions around -7%. The even bank goes up to around 25% (limit is 20%) so the MIL light is back on and off as this figure goes out of range. The odd lambda sensor is switching well. The even one goes lean and stays there at 0.1v. Rev it and it starts to switch until it idles again. Checked for air leaks on the manifold and exhaust.
The odd bank injector opening time is 2.7m/s and the evens 3.2m/s.
Have tried several throttle pots in various set ups and no different. Fitted 2 new coils as the spark time on 2 cylinders was way too high and this was cured. New plugs too and checked the leads using a spark tester tool and they are all good.
Tried setting the throttles closed by disconnecting the bar then fitting it so neither moved. Set the pots to 15% as per the software. Start up and she wont idle so adjust the stop again. Now will only idle at around 1,100 rpm and there is a lot more popping in the exhaust. Pots both read 19% at idle and go up together within 2% all the way.
Adaptions are now +4% odds, +26 evens.
So, after 4 hours to fit the sensors and another 4 trying to set the car up, can anyone help with:
1. a sequence of how to set the throttles from the beginning?
2. any ideas as to why the even bank adaptions are way out? (I've reset them after each adjustment along with the fault codes which is always AFR2468)?
3. why the throttle adaption cannot reach minimum?
Any help much appreciated. Thanks.
Without actually playing with car, looks to me like linkage and balance problems. Should be possible to set the throttle minimum position close to 15% on both banks and for it to idle without stalling. If you don't have the equipment and/or knowledge (no critism intended)to setup correctly well worth a trip to a local expert.
Englishman said:
Without actually playing with car, looks to me like linkage and balance problems. Should be possible to set the throttle minimum position close to 15% on both banks and for it to idle without stalling. If you don't have the equipment and/or knowledge (no critism intended)to setup correctly well worth a trip to a local expert.
I think he can handle it, he is competent (check the profile) How about a duff Sensor? Whats the wiring like, connectors are prone. Check with a scope to be sure?
While there may be other problems, it will only be possible to track thme down if you follow the setup procedure in the manual exactly step by step first, including measuring and balancing the flow in each bank. There are no shortcuts to doing this right.
Instructions here http://www.tvr-cerbera.co.uk/files/WorkshopManual/...
Once you have done that, clear the adaptives and the fault log and run it for a bit and tell us what comes up in the logs.
Instructions here http://www.tvr-cerbera.co.uk/files/WorkshopManual/...
Once you have done that, clear the adaptives and the fault log and run it for a bit and tell us what comes up in the logs.
Just got back to all these replies!
Okay, no flow gauge at present.
The crossover of the lambdas had not occurred to me but I did replace them one by one to ensure I got them the same way as before but of course this may be wrong. I will check this first when I get some time - Saturday now.
I cleared the fault log and the adaptives after each session so I was always starting from 0.
I have always thought this car should be quicker than it was so perhaps fixing this may resolve
the lack of performance. Fingers crossed.
I cannot take it to a specialist/TVR dealer as it would not go well with my job (pride). I will get it fixed, learning as I go. I don't give in....and as for me being competent, we'll see!
Thanks for the link to the manual. Your help is much appreciated men/ladies/etc
Okay, no flow gauge at present.
The crossover of the lambdas had not occurred to me but I did replace them one by one to ensure I got them the same way as before but of course this may be wrong. I will check this first when I get some time - Saturday now.
I cleared the fault log and the adaptives after each session so I was always starting from 0.
I have always thought this car should be quicker than it was so perhaps fixing this may resolve
the lack of performance. Fingers crossed.
I cannot take it to a specialist/TVR dealer as it would not go well with my job (pride). I will get it fixed, learning as I go. I don't give in....and as for me being competent, we'll see!
Thanks for the link to the manual. Your help is much appreciated men/ladies/etc
Edited by N7GTX on Thursday 21st November 23:32
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
When I had problems in the past have refered back to the thread above. It may or may not help
When I had problems in the past have refered back to the thread above. It may or may not help
scotty_d said:
Works even better if you can get a flow gauge on each bank when setting them up.
Ordered one from International Tool Company direct. Slightly cheaper than the Amazon link above.Need to get the power back as my M3 is making the Cerb seem slow
I am sure both lambdas are good, just the even bank is so far out, it cannot give a lower reading. Or they are wired the wrong way round.
Waiting for the flow gauge but thought I'd follow the settings instructions from the manual.
So, disconnected the throttle link rod, wound down the idle screw then set the throttle pots at 15%. Noticed there was a difference of 10 from min to max on the odd bank but just 5 on the even bank.
Removed the air box and compared the throttle positions on each side. They are different. So located the grub screw that holds the lever arm to the shaft and it was not very tight. I need to now set the arm then lock it to the throttle shaft at the correct position. Then I should get the same movement on both pots.
I think this may be causing the problem.
So, disconnected the throttle link rod, wound down the idle screw then set the throttle pots at 15%. Noticed there was a difference of 10 from min to max on the odd bank but just 5 on the even bank.
Removed the air box and compared the throttle positions on each side. They are different. So located the grub screw that holds the lever arm to the shaft and it was not very tight. I need to now set the arm then lock it to the throttle shaft at the correct position. Then I should get the same movement on both pots.
I think this may be causing the problem.
nemasis said:
Interesting that this manual is is quoted yet this was superceeded in the factory as this is NOT the correct procedure of setting the engine,we used to use this and then after a few set ups this was changed yet the manual was not, the way we were then shown how to set the engines in the factory was ,firstly the throttle pots should be adjusted to 16.9/17.1 on the primary throttle(different between 4.2 and 4.5) then adjust to 19.8/20.1 with the primary throttle and bring the secondary to that value using the throttle rod/bar. clamping of the purge pipe was deemed unnessasary, air flow adjust, using airflow meter was raised 5.0-6.0 kg/hour so each bank should be 20-24 kg/hour total. adjusting each side by either,alloy butterflies mark and file,and then retry, throttle adjust,using the throttle screw/bar(non alloy) or use air screws(non alloy) to equal each bank. I digress if the O/P would email me, tried to email you my number but you dont accept emails,i will talk you through the correct set up of an ajp v8(4.2 or 4.5,yes the set up WAS different)
Well the man has spoken. WTF he said though is anyone's guess! 
nemasis said:
Interesting that this manual is is quoted yet this was superceeded in the factory as this is NOT the correct procedure of setting the engine,we used to use this and then after a few set ups this was changed yet the manual was not, the way we were then shown how to set the engines in the factory was ,firstly the throttle pots should be adjusted to 16.9/17.1 on the primary throttle(different between 4.2 and 4.5) then adjust to 19.8/20.1 with the primary throttle and bring the secondary to that value using the throttle rod/bar. clamping of the purge pipe was deemed unnessasary, air flow adjust, using airflow meter was raised 5.0-6.0 kg/hour so each bank should be 20-24 kg/hour total. adjusting each side by either,alloy butterflies mark and file,and then retry, throttle adjust,using the throttle screw/bar(non alloy) or use air screws(non alloy) to equal each bank. I digress if the O/P would email me, tried to email you my number but you dont accept emails,i will talk you through the correct set up of an ajp v8(4.2 or 4.5,yes the set up WAS different)
Fascinating, thank you very much for sharing that - I never knew there was any procedure other than the one in the manual. Perhaps it would explain why the published method is so hit and miss. Could you elaborate on what the difference between the 4.2 and 4.5 setups is. It would be great to be able to document the correct factory method for future reference.
nemasis said:
well go to the link for the workshop manual read its set up and then read what i have put, its not difficult,but who am i to go against what has been put on here!!!!!
Mark. said:
Well the man has spoken. WTF he said though is anyone's guess!
nemasis said:
read what i have put, its not difficult,
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