V8S running problems
Discussion
Hi all, having a bit of early bad luck with my V8S. It's running terribly, very rich, and recently started stuttering / shunting on the move and stalling at junctions. Idle is hunting badly when warm, stinks of unburnt / rich fumes, black smoke from exhaust. Runs ok for first minute or two when cold so I'm inclined to think fuelling.
Car had quite extensive work before I took delivery, including a new cam, servo, brakes, fuel lines, full 12k service inc new plugs and fuel / air filter.
Since I've had it, idle hasnt been too great and have been methodically working through items with the help of the TVR place that did the work (a long, long way away!!)
So far, following has been checked / replaced:
New TVR stepper, gasket fine
New AFM (borrowed) and voltages check out fine on new and old
Throttle pot adjusted to 0.33v and rises smoothly
Fuel pressure spot on and vacuum reduces it on regulator
New HT leads, rotor arm, cap and coil from Powerspark (Simon BBC)
New Lucas amplifier
Checked extensively for vacuum leaks, none
Compression just over 150
All cylinders firing (checked with strobe and inline indicators)
Reset base idle
New coolant temperate sensor
Vacuum and mechanical advance all working on dizzy
Rovergauge shows all parameters as OK, all sensor readings look sensible on RG, ECU is clearly getting the right data.
Must admit I'd expected a few challenges with an S but this is baffling me now and getting quite frustrated. Any ideas on what else I could check out before throwing it at a specialist?
Cheers
Car had quite extensive work before I took delivery, including a new cam, servo, brakes, fuel lines, full 12k service inc new plugs and fuel / air filter.
Since I've had it, idle hasnt been too great and have been methodically working through items with the help of the TVR place that did the work (a long, long way away!!)
So far, following has been checked / replaced:
New TVR stepper, gasket fine
New AFM (borrowed) and voltages check out fine on new and old
Throttle pot adjusted to 0.33v and rises smoothly
Fuel pressure spot on and vacuum reduces it on regulator
New HT leads, rotor arm, cap and coil from Powerspark (Simon BBC)
New Lucas amplifier
Checked extensively for vacuum leaks, none
Compression just over 150
All cylinders firing (checked with strobe and inline indicators)
Reset base idle
New coolant temperate sensor
Vacuum and mechanical advance all working on dizzy
Rovergauge shows all parameters as OK, all sensor readings look sensible on RG, ECU is clearly getting the right data.
Must admit I'd expected a few challenges with an S but this is baffling me now and getting quite frustrated. Any ideas on what else I could check out before throwing it at a specialist?
Cheers
GreenV8S said:
Do you mean sparking?
Got me thinking though, wonder if I should put different / new plugs back in, have ones from pre service which clearly haven’t done many miles. Interestingly the TVR place put BP7ES in, old ones were B7ECS. Would that make any difference? Thanks all.
I suspect you have several problems here, possibly caused by all the new parts.
Check the inside of the distributor cap. I've seen a "new" one recently that had plastic over some of the terminals and the wear pattern after just a few miles showed that whilst some of the terminals were in contact with the rotor arm others weren't. So clearly it wasn't perfectly circular.
You could also try removing the gasket on the stepper motor. If it is too thick it will cause problems.
Are you getting any weird error messages on RG (68 maybe)? When the wiring on my speedo was wearing through I had a lot of running problems similar to some of those you describe.
Check the inside of the distributor cap. I've seen a "new" one recently that had plastic over some of the terminals and the wear pattern after just a few miles showed that whilst some of the terminals were in contact with the rotor arm others weren't. So clearly it wasn't perfectly circular.
You could also try removing the gasket on the stepper motor. If it is too thick it will cause problems.
Are you getting any weird error messages on RG (68 maybe)? When the wiring on my speedo was wearing through I had a lot of running problems similar to some of those you describe.
Thanks all this is really useful stuff.
I'll try the resistor - can't wait to unravel that mess again (!!!) - it's a precat and on RG it's clearly running map 2 which is the correct one.
There are no fault codes, but the comment about the speedo wiring is interesting, as the speedo sometimes doesn't activate for the first few hundred yards if weather is very cold, but then kicks in absolutely fine, I'd put it down to cold viscous oil affecting the sensor drive. Whereabouts had it worn through?
I might also put back all the old ignition kit as it clearly wasn't the original cause of the issue, just to eliminate any faulty new components.
Thanks again - maybe not quite ready for a trailer to a specialist!!
I'll try the resistor - can't wait to unravel that mess again (!!!) - it's a precat and on RG it's clearly running map 2 which is the correct one.
There are no fault codes, but the comment about the speedo wiring is interesting, as the speedo sometimes doesn't activate for the first few hundred yards if weather is very cold, but then kicks in absolutely fine, I'd put it down to cold viscous oil affecting the sensor drive. Whereabouts had it worn through?
I might also put back all the old ignition kit as it clearly wasn't the original cause of the issue, just to eliminate any faulty new components.
Thanks again - maybe not quite ready for a trailer to a specialist!!
On mine the speedo wires chaffed through on the top edge of the gear box. Mine is lazy on cold mornings as well so don't worry about it (I've replaced the sensor and the wiring and it still does it).
If you've been pulling the loom about you could also check the permanent live feed connection on the loom to the ECU. It's just a soldered joint on to a wire so it can dry out and intermittently fail. Although a fault like this would throw up the relevant error code (02 I believe).
Refitting the old parts might be a good idea but do it systematically ie one part at a time and checking for any difference after each step.
Beware of "specialists"
Some know what they are doing, others specialise in replacing components and hoping the problem will go away long enough for the customer to cough up and go away.
If you've been pulling the loom about you could also check the permanent live feed connection on the loom to the ECU. It's just a soldered joint on to a wire so it can dry out and intermittently fail. Although a fault like this would throw up the relevant error code (02 I believe).
Refitting the old parts might be a good idea but do it systematically ie one part at a time and checking for any difference after each step.
ajfspencer said:
T......maybe not quite ready for a trailer to a specialist!!
Beware of "specialists"
Some know what they are doing, others specialise in replacing components and hoping the problem will go away long enough for the customer to cough up and go away.Edited by v8s4me on Monday 15th April 14:27
I wouldn't completely rule out Rover V8 Specialists with long and good history like:
John Eales
Claybrooke Mill
Frolesworth Lane
Claybrooke Magna
Leicestershire
LE17 5DB
01455 202909
email: rv8@btconnect.com
V8 Developments is located in South Lincolnshire, UK.
We are within easy reach of the A1, A52, A16, A17.
V8Developments Ltd.
Cobwebbs Farm
Swale Bank
Gosberton Westhorpe
Spalding
Lincolnshire
PE11 4LG
Tel: 01775 750000
John Eales
Claybrooke Mill
Frolesworth Lane
Claybrooke Magna
Leicestershire
LE17 5DB
01455 202909
email: rv8@btconnect.com
V8 Developments is located in South Lincolnshire, UK.
We are within easy reach of the A1, A52, A16, A17.
V8Developments Ltd.
Cobwebbs Farm
Swale Bank
Gosberton Westhorpe
Spalding
Lincolnshire
PE11 4LG
Tel: 01775 750000
Thank you. J Eales is very close and while I wouldn't want to drive it there maybe we can find a way round it if needed after I've exhausted all my avenues.
After some overnight reflection, and stepping away from the frustration for a while (always a good thing), I have realised one thing off the Rovergauge that I hadn't noted - I don't think idle conditions are being met. The green light isn't on with a target rpm. So while no fault codes, something isn't triggering the idle conditions. Therefore v8s4me's point about speedo wiring (must be speed sensor as well) is worth a check.
So there's a few things to keep me occupied in the evenings this week!!
Cheers
After some overnight reflection, and stepping away from the frustration for a while (always a good thing), I have realised one thing off the Rovergauge that I hadn't noted - I don't think idle conditions are being met. The green light isn't on with a target rpm. So while no fault codes, something isn't triggering the idle conditions. Therefore v8s4me's point about speedo wiring (must be speed sensor as well) is worth a check.
So there's a few things to keep me occupied in the evenings this week!!
Cheers
Your MAF reading looks a bit high. This is the last RG image off mine for comparison (May 2017 - pre-CAT)...
I thought I had a copy of last years but can't find it at the moment. I don't think there was any significant difference.
A faulty AFM would cause some of the symptoms you describe.
I thought I had a copy of last years but can't find it at the moment. I don't think there was any significant difference.
A faulty AFM would cause some of the symptoms you describe.
v8s4me said:
Your MAF reading looks a bit high. This is the last RG image off mine for comparison (May 2017 - pre-CAT)...
I thought I had a copy of last years but can't find it at the moment. I don't think there was any significant difference.
A faulty AFM would cause some of the symptoms you describe.
Thanks for this comparison, really useful, I think the MAF difference is that you are in a different RG mode (linear vs direct) - think my reading is same as yours in linear mode. Plus have tried a brand new Lucas MAF and no difference.I thought I had a copy of last years but can't find it at the moment. I don't think there was any significant difference.
A faulty AFM would cause some of the symptoms you describe.
But look....yours says manual gearbox, and you have idle mode in green. Mine looks like it thinks it's an auto in drive or reverse, no idle mode green light. So a double check again of throttle pot and speed sensor wiring.
I really appreciate all this help!
v8s4me said:
Your MAF reading looks a bit high. This is the last RG image off mine for comparison (May 2017 - pre-CAT)...
I thought I had a copy of last years but can't find it at the moment. I don't think there was any significant difference.
A faulty AFM would cause some of the symptoms you describe.
I think you either have a land rover 4.2 ecu or your ecu was remapped around a 3116 file, which I don't think tvr ever used .. ?I thought I had a copy of last years but can't find it at the moment. I don't think there was any significant difference.
A faulty AFM would cause some of the symptoms you describe.
See steve sprint's 14cux remapping site for variations of the chip file versions.
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