Tuscan Misfire
Discussion
Afternoon all, looking for a bit of advice.
Having previously been a Chim owner some 8 years ago and upon deciding to put less miles on my Esprit I took the plunge last year and bought a 2001 4.0 Tuscan.
Obviously the intervening 8 years had meant that I had forgotten how frustrating TVR ownership can be but alas I was soon reminded when the Tuscan developed an intermittent misfire.
This first manifested itself when I got stuck in some road works last summer but soon cleared itself when back up to speed.
I thought nothing much more of it until around October/November when the misfire became so bad that it rendered the car undrivable. Interestingly this particular time the misfire started after a trip out when I returned through town and ended up getting caught on red at every traffic light. Although I assumed that the problem would have disappeared the next time I started the car this was not the case and the car kept stalling and was running on three cylinders.
I replaced the coil pack and leads myself but that made no odds. Off it went to a garage who spent a lot of time going over it and identified that it was probably caused by water in the fuel and a faulty fuel pressure regulator. Car ran sweet as a nut when I picked it up but alas, as soon as I hit town it started to miss very lightly. I thought this was maybe my mind playing tricks but surprise surprise the next time I went out in it it did the same again but was really bad this time and took a good 10 miles to clear (hope the cats are ok).
Now I’ve had the car out again this weekend, covering about 500 miles in total from Carlisle to Fort William and back. Car runs superb on the open road but as soon as it sits with the engine running for more than 10 seconds it starts to miss. Again upon starting it up the next day it was missing again.
I was therefore wondering if anybody else has encountered something similar. I am wondering if the lambda sensors are getting coked up and that’s the cause of it but the garage did check them and said they were switching ok.
Any advice would be much appreciated before I decided to chop it in for something else.
Back ground - car has done 56,400 miles, I’ve done just over 3k since I got it. Engine rebuild at str8six about 12k miles ago.
Cheers
Chris
Having previously been a Chim owner some 8 years ago and upon deciding to put less miles on my Esprit I took the plunge last year and bought a 2001 4.0 Tuscan.
Obviously the intervening 8 years had meant that I had forgotten how frustrating TVR ownership can be but alas I was soon reminded when the Tuscan developed an intermittent misfire.
This first manifested itself when I got stuck in some road works last summer but soon cleared itself when back up to speed.
I thought nothing much more of it until around October/November when the misfire became so bad that it rendered the car undrivable. Interestingly this particular time the misfire started after a trip out when I returned through town and ended up getting caught on red at every traffic light. Although I assumed that the problem would have disappeared the next time I started the car this was not the case and the car kept stalling and was running on three cylinders.
I replaced the coil pack and leads myself but that made no odds. Off it went to a garage who spent a lot of time going over it and identified that it was probably caused by water in the fuel and a faulty fuel pressure regulator. Car ran sweet as a nut when I picked it up but alas, as soon as I hit town it started to miss very lightly. I thought this was maybe my mind playing tricks but surprise surprise the next time I went out in it it did the same again but was really bad this time and took a good 10 miles to clear (hope the cats are ok).
Now I’ve had the car out again this weekend, covering about 500 miles in total from Carlisle to Fort William and back. Car runs superb on the open road but as soon as it sits with the engine running for more than 10 seconds it starts to miss. Again upon starting it up the next day it was missing again.
I was therefore wondering if anybody else has encountered something similar. I am wondering if the lambda sensors are getting coked up and that’s the cause of it but the garage did check them and said they were switching ok.
Any advice would be much appreciated before I decided to chop it in for something else.
Back ground - car has done 56,400 miles, I’ve done just over 3k since I got it. Engine rebuild at str8six about 12k miles ago.
Cheers
Chris
Edited by Chris-xzk0j on Monday 26th February 14:25
My throttle bodies are leaking and it’s rough at idle but not at revs, but it doesn’t change. The roughness is always present at idle. An easy test is to spray the area where the throttle bodies meet the head with easy start while it’s idling. If the revs increase you’ve got a leak. The throttle body spindles are also known to leak air when worn.
I doubt it’s lambda sensors if it is doing it the moment you start up. I’m no Tuscan expert but every lambda controlled ECU I’ve worked on doesn’t use them for the first 30 seconds or so. They need to be heated by an internal coil to work properly and this takes a little while so the ECU ignores them after start.
Do you know the garage fitted the right plugs? The symptoms you describe do sound like plug fouling. Either from the wrong plug or from too much fuel or oil. Maybe they fixed one problem and caused another.
When were the throttle bodies last balanced could be that some cylinders aren’t getting enough air at idle.
The Speed Six diagnostic software is freely available and just needs a cable to run with your laptop.
I doubt it’s lambda sensors if it is doing it the moment you start up. I’m no Tuscan expert but every lambda controlled ECU I’ve worked on doesn’t use them for the first 30 seconds or so. They need to be heated by an internal coil to work properly and this takes a little while so the ECU ignores them after start.
Do you know the garage fitted the right plugs? The symptoms you describe do sound like plug fouling. Either from the wrong plug or from too much fuel or oil. Maybe they fixed one problem and caused another.
When were the throttle bodies last balanced could be that some cylinders aren’t getting enough air at idle.
The Speed Six diagnostic software is freely available and just needs a cable to run with your laptop.
Edited by Oneball on Monday 26th February 16:43
Agree with Oneball.
Get TB's checked/balanced. Maybe do "EasyStart" test around TB flanges and spindles.
Check plug condition and correct type. Check also routing of HT leads to coil pack, seem to remember someone posting on here about HT leads proximity to crank position sensor causing issues.
I would also check 'aircraft-type' connector from engine loom through bulkhead for pin condition/corrosion...spray with contact cleaner.
Above fairly easy to DIY with simple tools.
Nick
Get TB's checked/balanced. Maybe do "EasyStart" test around TB flanges and spindles.
Check plug condition and correct type. Check also routing of HT leads to coil pack, seem to remember someone posting on here about HT leads proximity to crank position sensor causing issues.
I would also check 'aircraft-type' connector from engine loom through bulkhead for pin condition/corrosion...spray with contact cleaner.
Above fairly easy to DIY with simple tools.
Nick
Hard to tell what is going on but I wouldn't ditch what may be a superb car for a possibly minor problem.
I can commend
MBE Diagnostic tool with software from Oliver Wiechens (EvoOlli on here) - plugs straight into MBE unit - gives so many parameters - not a diagnosis on a plate but will give important clues.
Going for an annual service at a known TVR specialist - I share the pain at being in SW Scotland, some distance from the specialists, but there are several of us who make the journey and consider it well worthwhile. Those within reach include HHC in Hexham, and X-works near Preston.
I can commend
MBE Diagnostic tool with software from Oliver Wiechens (EvoOlli on here) - plugs straight into MBE unit - gives so many parameters - not a diagnosis on a plate but will give important clues.
Going for an annual service at a known TVR specialist - I share the pain at being in SW Scotland, some distance from the specialists, but there are several of us who make the journey and consider it well worthwhile. Those within reach include HHC in Hexham, and X-works near Preston.
Thanks for the advice chaps, few things to consider there so first of all I think I might whip the plugs out after a spirited drive then again after I’ve left it running on the drive and see if there are any signs of them fouling up.
Will probably have to get myself the software too to read the ecu.
The car has actually been to a couple of specialists since I’ve had it and although I can’t fault either of them in any way as they have been very thorough, helpful and professional I guess my concern is throwing a lot more cash at an intermittent fault that will probably end up being something really simple.
I had similar problems with my last tvr and it took the shine off owning it. I’ve already gone through two throttle cables, the first one snapping on only my second trip out on in the car resulting in a 40mile drive home with a hand throttle! The other concern is how twitchy and unstable the car feels, especially at speed but I guess this can be sorted with more time and money. It is a glorious beast though even if I do find the Esprit a more reliable (I’ve cursed myself now) and competent vehicle.
Will probably have to get myself the software too to read the ecu.
The car has actually been to a couple of specialists since I’ve had it and although I can’t fault either of them in any way as they have been very thorough, helpful and professional I guess my concern is throwing a lot more cash at an intermittent fault that will probably end up being something really simple.
I had similar problems with my last tvr and it took the shine off owning it. I’ve already gone through two throttle cables, the first one snapping on only my second trip out on in the car resulting in a 40mile drive home with a hand throttle! The other concern is how twitchy and unstable the car feels, especially at speed but I guess this can be sorted with more time and money. It is a glorious beast though even if I do find the Esprit a more reliable (I’ve cursed myself now) and competent vehicle.
Mine was hideous to drive on anything other than a billiard table when I got it. There’s a road by my sister’s house where the edge has subsided and anything over 40mph was danagerous. The car was basically steering itself due to bump steer, when front suspension compressed this caused toe in. A car really should toe out in bump as this compensates for the lateral force generated by the camber gain from compressing One wheel and helps it run straight (advice from a friend who is an ex Lotus/Aston Martin chassis engineer).
To sort this I’ve raised the rack, I’ve got a total of 9mm of spacers under it and completed a full geo setup. The rack could do with being a bit higher, but there’s no clearance however it now drives nicely at any speed.
Don’t listen to the specialists who bang on about shocks. They fit adjustables and wind them right up so the suspension basically doesn’t move.
A lot of cars run way lower than designed and this makes the bump steer worse.
There could be other reasons but the above sorted mine, it’s a 2002 car.
I bought my Tuscan instead of an Esprit. I’d wanted a Peter Stevens Turbo since they came out and had a test drive of a really late pre-S4 and was utterly disappointed. It drove like an 80s Ferrari the clutch was ridiculously heavy and gear change awful. I was assured that’s what their all like by a Lotus specialist, is that true?
To sort this I’ve raised the rack, I’ve got a total of 9mm of spacers under it and completed a full geo setup. The rack could do with being a bit higher, but there’s no clearance however it now drives nicely at any speed.
Don’t listen to the specialists who bang on about shocks. They fit adjustables and wind them right up so the suspension basically doesn’t move.
A lot of cars run way lower than designed and this makes the bump steer worse.
There could be other reasons but the above sorted mine, it’s a 2002 car.
I bought my Tuscan instead of an Esprit. I’d wanted a Peter Stevens Turbo since they came out and had a test drive of a really late pre-S4 and was utterly disappointed. It drove like an 80s Ferrari the clutch was ridiculously heavy and gear change awful. I was assured that’s what their all like by a Lotus specialist, is that true?
Edited by Oneball on Tuesday 27th February 09:02
I had read about putting some spacers in the rack but didn’t realise it need quite so much of a lift.
As for shocks ie Nitrons do you think they are a waste of time them?
With regards to the Esprit I can confirm that the gear change is a dog on mine too (98 GT3) is a bit better since I had some upgraded bushes and linkages put in but still not brilliant and does almost spoil the drive. But that being said it just feels so benign compared to the TVR (lot less power and torque I know) and when you do start to press on it just seems to hunker down rather than lift like the Tuscan.
As for my favourite car to take out for a drive up Hartside...ZS 180...totally underrated machine
As for shocks ie Nitrons do you think they are a waste of time them?
With regards to the Esprit I can confirm that the gear change is a dog on mine too (98 GT3) is a bit better since I had some upgraded bushes and linkages put in but still not brilliant and does almost spoil the drive. But that being said it just feels so benign compared to the TVR (lot less power and torque I know) and when you do start to press on it just seems to hunker down rather than lift like the Tuscan.
As for my favourite car to take out for a drive up Hartside...ZS 180...totally underrated machine
Edited by Chris-xzk0j on Tuesday 27th February 20:13
Something you said about running on 3 cylinders.
If you plug the free software in you will be able to see whilst engine running. When I had similar to what you describe I could see that tps (throttle position sensor) no2 was erratic. The ecu treats the engine as 2 x 3cyl.
Of course no2 is the one right at the back of the engine but still possible to get to.
Also it is a Ford part from a V6 granada scorpio.
Hope this helps
If you plug the free software in you will be able to see whilst engine running. When I had similar to what you describe I could see that tps (throttle position sensor) no2 was erratic. The ecu treats the engine as 2 x 3cyl.
Of course no2 is the one right at the back of the engine but still possible to get to.
Also it is a Ford part from a V6 granada scorpio.
Hope this helps
I don’t think decent shocks are a waste of time, just that they don’t cure bump steer.
I’ve got Nitrons on mine, shocks are good but I find the springs are a little stiff. I think the factory fit springs and shocks are too soft, so am looking for a compromise.
The mk1 Tuscans were set up to be relatively soft, have a look at an original road test on YouTube, they do move around a lot and are prone to oversteer with sudden changes of direction.
Until I’d sorted mine I didn’t like making progress in it and would back off at modest speeds.
I’ve got Nitrons on mine, shocks are good but I find the springs are a little stiff. I think the factory fit springs and shocks are too soft, so am looking for a compromise.
The mk1 Tuscans were set up to be relatively soft, have a look at an original road test on YouTube, they do move around a lot and are prone to oversteer with sudden changes of direction.
Until I’d sorted mine I didn’t like making progress in it and would back off at modest speeds.
Edited by Oneball on Wednesday 28th February 07:50
Chris-xzk0j said:
I had read about putting some spacers in the rack but didn’t realise it need quite so much of a lift.
As for shocks ie Nitrons do you think they are a waste of time them?
It depends whether your car was pre or post March 2001, ie has the narrow or wider rack. If it's earlier then it's hard to correct the bump steer over a decent amount of travel due to the track rod length.As for shocks ie Nitrons do you think they are a waste of time them?
The standard suspension is under sprung and over damped, so it bounces around on small bumps and then bottoms out on big ones. Nitrons make it a lot better but I understand the newer kits are a bit more track focused than the original kits like I have, so even firmer.
For decent ride and springs that aren't too stiff, consider the Tuscan S Bilstien spring and dampers. The rears springs are about halfway between the old soft springs and Sagaris/nitron spring rates. And the Billies have nice bump compliance. If your pressing on on roads with whoops and dips then the rears may still feel a little soft (hits the bump stops) but a lot better than the old stock setup. Blackdown Auto should be able source a set (or most TVR specialists).
PS if your still searching for misfire fix, my T350 needed plugs, leads, TPS pots and lambdas (they were knackerd so swapped anyway) . and a new coil as my old one had some cracks to cure plug fouling /misfire. One thing was it didn't like NGK iridium plugs and ran better on standard spec NGKs.
PS if your still searching for misfire fix, my T350 needed plugs, leads, TPS pots and lambdas (they were knackerd so swapped anyway) . and a new coil as my old one had some cracks to cure plug fouling /misfire. One thing was it didn't like NGK iridium plugs and ran better on standard spec NGKs.
Edited by fredd1e on Wednesday 28th February 13:32
Thanks for the extra info lads, I will have a look at the TPS when I get the software and the time.
Will have to give the suspension some serious thought, again once I have the time. My friend has a Chim at the minute and he ended up putting nitrons on it and said it was the best investment he had made.
Will have to give the suspension some serious thought, again once I have the time. My friend has a Chim at the minute and he ended up putting nitrons on it and said it was the best investment he had made.
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