Intermittent missfire

[adamsclan]

I think Keyser is on the right track, and i would go a bit further and hazard a guess that the APS being a piggyback and used for the VQ will be intercepting an altering the lambda feedback thats sent to the ECU, i suspect that its this that screwing up the feedback signal to the ECU and causing your problems.

As I discussed with Keyser, The crank sensor wire supplied with the APS kit appears not to have been fitted (shielded to stop any EM scatter) or else has been spliced into the wiring away from the crank sensor - why I have no idea. The problem is that there is now only one dealer for APS ie DS Automotives, some 450 miles away. I have been trying to find a tuner nearer to my home in Dundee who would be knowledgeable enough to ascertain whether it is an ECU/piggyback problem, but to no avail. I shall try Keyser's suggestion but if it is as you say can you suggest a solution. I noticed that the crank sensor wire goes into the same sleeve as the exhaust lambda sensors, which is what the kit-supplied separate shielded cable is to prevent. There is no way I have sufficient knowledge or courage to try to separate wiring systems or re-wire components. The question remains why should the car/TT kit work perfectly for 35k miles/5.5 years then do this? On 2nd thoughts I'll just be happy for someone to fix the problem. Cheers

[adamsclan]

either get the stock ECU remapped for it or run a standalone ECU, piggybacks are never the best solution.

I've considered this but can't find anywhere locally to get this done. Anybody with any ideas?

[Tricky-Ricky]

I think Keyser is on the right track, and i would go a bit further and hazard a guess that the APS being a piggyback and used for the VQ will be intercepting an altering the lambda feedback thats sent to the ECU, i suspect that its this that screwing up the feedback signal to the ECU and causing your problems.

As I discussed with Keyser, The crank sensor wire supplied with the APS kit appears not to have been fitted (shielded to stop any EM scatter) or else has been spliced into the wiring away from the crank sensor - why I have no idea. The problem is that there is now only one dealer for APS ie DS Automotives, some 450 miles away. I have been trying to find a tuner nearer to my home in Dundee who would be knowledgeable enough to ascertain whether it is an ECU/piggyback problem, but to no avail. I shall try Keyser's suggestion but if it is as you say can you suggest a solution. I noticed that the crank sensor wire goes into the same sleeve as the exhaust lambda sensors, which is what the kit-supplied separate shielded cable is to prevent. There is no way I have sufficient knowledge or courage to try to separate wiring systems or re-wire components. The question remains why should the car/TT kit work perfectly for 35k miles/5.5 years then do this? On 2nd thoughts I'll just be happy for someone to fix the problem. Cheers

 

 

Just been having a read of the APS blurb about the kit fitted, it appears to use an American unichip, with non user editable maps,

a rising rate FPR, and did you say it was fitted with a MAP sensor? and is this used instead of or in conjunction with the AFM?

 

The non connection of the crank sensor should have no effect if its never been connected, i would guess that side is all handled by the std ECU, there are a number of things that will effect how the engine runs, but as your problem is intermittent it limits the possible causes, the first thing that you can check is the vacuum line to the FPR, although i doubt thats solely responsible, but the reg itself could be,

 

As i said before the AP piggyback will almost certainly modify the std Lambda feedback signal in order to fool the std ECU into thinking that its still running the pre programed AFRs when its really running much richer fueling, so that is certainly a place where things could also go wrong, however if the std lambda sensors are going outside the expected readings it should show up via a fault code,

 

Its a difficult one to diagnose without more info, i have no problem with piggybacks in general ( and have used several in the past to very good results) but i am not a fan of these all in one kits that use a piggyback made and mapped by a third party.

[adamsclan]

I think Keyser is on the right track, and i would go a bit further and hazard a guess that the APS being a piggyback and used for the VQ will be intercepting an altering the lambda feedback thats sent to the ECU, i suspect that its this that screwing up the feedback signal to the ECU and causing your problems.

As I discussed with Keyser, The crank sensor wire supplied with the APS kit appears not to have been fitted (shielded to stop any EM scatter) or else has been spliced into the wiring away from the crank sensor - why I have no idea. The problem is that there is now only one dealer for APS ie DS Automotives, some 450 miles away. I have been trying to find a tuner nearer to my home in Dundee who would be knowledgeable enough to ascertain whether it is an ECU/piggyback problem, but to no avail. I shall try Keyser's suggestion but if it is as you say can you suggest a solution. I noticed that the crank sensor wire goes into the same sleeve as the exhaust lambda sensors, which is what the kit-supplied separate shielded cable is to prevent. There is no way I have sufficient knowledge or courage to try to separate wiring systems or re-wire components. The question remains why should the car/TT kit work perfectly for 35k miles/5.5 years then do this? On 2nd thoughts I'll just be happy for someone to fix the problem. Cheers

 

 

Just been having a read of the APS blurb about the kit fitted, it appears to use an American unichip, with non user editable maps,

a rising rate FPR, and did you say it was fitted with a MAP sensor? and is this used instead of or in conjunction with the AFM?

 

The non connection of the crank sensor should have no effect if its never been connected, i would guess that side is all handled by the std ECU, there are a number of things that will effect how the engine runs, but as your problem is intermittent it limits the possible causes, the first thing that you can check is the vacuum line to the FPR, although i doubt thats solely responsible, but the reg itself could be,

 

As i said before the AP piggyback will almost certainly modify the std Lambda feedback signal in order to fool the std ECU into thinking that its still running the pre programed AFRs when its really running much richer fueling, so that is certainly a place where things could also go wrong, however if the std lambda sensors are going outside the expected readings it should show up via a fault code,

 

Its a difficult one to diagnose without more info, i have no problem with piggybacks in general ( and have used several in the past to very good results) but i am not a fan of these all in one kits that use a piggyback made and mapped by a third party.

I was told by Dave of DS Automotives that APS do now use a Unichip but my kit was supplied with the previous engine management piggy-back. I have no idea what make it is as it had only the APS logo on it.

I'm assuming the crank sensor is still connected though thro' the original wire and not the replacement kit-supplied shielded cable, else why would APS have this cale specifically included in the kit.

I'm going to show my ignorance now but what is the "FPR"? Your reference to MAP, I think I was referring to the MAF - mass air flow sensor - maybe a typo on my part!

I have found a company called RS Tuning not far from my home and I recall Keyser referring to them. Does anyone have knowledge of them? I have no wish to question their professionalism or skills it's just that it seems so many of the so-called "tuning" companies are iffy to say the least.

[Tricky-Ricky]

Yes the std ECU will be reading the std crank sensor, and taking care of all the basic stuff so no need for the piggyback sensor connection in theory as it should be picking up that from the ECU anyway,

 

FPR (fuel pressure regulator) will have been replaced for a rising rate item, this will be connected to a port on the plenum somewhere by some small bore hose, its worth checking this for leaks etc, it basically increases the fuel pressure with the onset of boost,

 

I asked if it was still ruining the std MFA or a MAP (manifold absolute pressure) sensor, or both? my reason for the question was because if its still using the std (or aftermarket?) MAF this to will be having the output altered by the piggyback so another place for problems,

 

Again i am not saying that piggybacks are a problem, but it does make for an extra work when checking for problems.

 

Is there anything else you notice when the problem occurs?

 

Cant hep with RS, i know RK tuning, what area do you live? and who did the original conversion?

[adamsclan]

Yes the std ECU will be reading the std crank sensor, and taking care of all the basic stuff so no need for the piggyback sensor connection in theory as it should be picking up that from the ECU anyway,

 

FPR (fuel pressure regulator) will have been replaced for a rising rate item, this will be connected to a port on the plenum somewhere by some small bore hose, its worth checking this for leaks etc, it basically increases the fuel pressure with the onset of boost,

 

I asked if it was still ruining the std MFA or a MAP (manifold absolute pressure) sensor, or both? my reason for the question was because if its still using the std (or aftermarket?) MAF this to will be having the output altered by the piggyback so another place for problems,

 

Again i am not saying that piggybacks are a problem, but it does make for an extra work when checking for problems.

 

Is there anything else you notice when the problem occurs?

 

Cant hep with RS, i know RK tuning, what area do you live? and who did the original conversion?

FPR standard unit has been replaced "In order to ensure precise fuel pressure delivery at high horsepower levels, a 4.0 Bar fuel pressure regulator replaces the stock 3.5 Bar unit. In addition the APS fuel pressure regulator is vacuum/pressure referenced to the engine's intake manifold, therefore the regulator is mounted on the outside of the stock fuel pump/sender unit - and housed in a custom high flow housing assembly. In this way, fuel pressure across each injector orifice is maintained at a constant level regardless of the turbocharger boost pressure level - a configuration as found in the world's best turbocharged high performance production engines. Best of all, the restriction caused by the stock 3.5 Bar regulator is removed completely and a new custom replacement plug is included to facilitate this". Quote from Air Power Systems website.

I am really struggling with the details you describe as I am a complete novice when it comes to FI systems.

I thimk I have fairly well described the nature of the intermittent fault but there may well be stuff going on which I do recognise as inportant or would give further clues. A specialist nearby would probably be the best eay to go.

I live in Dundee and the conversion was carried out by WRC at Silverstone now unfortunately defunct. DS Automotives are now the only company in the UK to carry out the conversion.

All I wanted was a bolt-on system which gave better accelaration and was (as proven for 35k miles) reliable.

[Tricky-Ricky]

OK cant really help without more feedback, so your best bet is then a specialist tuner/engineer, however i think your just going to have to go on recommendation/reputation, and probably travel some distance to get it sorted, i certainly wouldn't trust it to any average garage/tuning shop.

[adamsclan]

OK cant really help without more feedback, so your best bet is then a specialist tuner/engineer, however i think your just going to have to go on recommendation/reputation, and probably travel some distance to get it sorted, i certainly wouldn't trust it to any average garage/tuning shop.

If you pm me your phone number perhaps I could give you the feedback/info you require. Thanks for your help.

[adamsclan]

Sent pm to Zmanalex as suggested by a member. Hopefully he will be able to help me in my quest! Is his broadband still playing up?

[Ebized]

Sent pm to Zmanalex as suggested by a member. Hopefully he will be able to help me in my quest! Is his broadband still playing up?

 

Having recommended you to approach Alex, knowing his experience with TT conversions and that he was relatively local, I since understand you have previously sought his advice but chose other options after pm exchanges so I think you will need to continue to look elsewhere.

[adamsclan]

Sent pm to Zmanalex as suggested by a member. Hopefully he will be able to help me in my quest! Is his broadband still playing up?

 

Having recommended you to approach Alex, knowing his experience with TT conversions and that he was relatively local, I since understand you have previously sought his advice but chose other options after pm exchanges so I think you will need to continue to look elsewhere.

I may well be a relative novice to this forum re postings, pm's, etc. but it strikes me as a sad state of affairs when one is stopped from being helped because a previous situation was resolved via another route. Perhaps I didn't show the proper etiquette - as it turned out, the problem i pm'd Alex about wasn't actually the problem. So what does this mean? I can't communicate with Alex re any future need for parts or repairs when he seems the ideal chap to help? Having been in business previously for some 25 years it doesn't seem very helpful or sensible from a business point of view. Alex, if you feel slighted by my previous communications I can assure you no slight was intended. Tell you what, phone me on 01382 737769 if you want to have the creck!

[Ebized]

You are not being "stopped from being helped" but there comes a point when everyone in business has to draw a line on time spent on advice when they have other customers to deal with.

 

In my own line of work I too have to 'draw the line' with those who just try to use me for getting free info to then go off and do it themselves, often later on getting into difficulties and wanting me to bail them out........When a living has to be made there comes a time when we all have to draw a line rather than becoming an extension of the Citzens Advice Bureau.

 

But you get plenty of advice on here and good to see others who have the time are offering their advice to you for free.

[adamsclan]

You are not being "stopped from being helped" but there comes a point when everyone in business has to draw a line on time spent on advice when they have other customers to deal with.

 

In my own line of work I too have to 'draw the line' with those who just try to use me for getting free info to then go off and do it themselves, often later on getting into difficulties and wanting me to bail them out........When a living has to be made there comes a time when we all have to draw a line rather than becoming an extension of the Citzens Advice Bureau.

 

But you get plenty of advice on here and good to see others who have the time are offering their advice to you for free.

I thoroughly appreciate the advice given to me by all the members who responded and would hope I have responded accordingly. But when I no longer required the said item, some 17 months ago, I was not aware the trader would then refuse to have any future dealings with me. I cannot recall wasting anyone's time nor "just try to use me for getting free info to then go off and do it themselves". Anyway I guess I shall just have to pursue a solution to my car's problems in some far-flung place. Pity - potentially time & travel saved for me and business for another. The offer of communication to resolve is still on the table. And thanks for your assistance.

[scubapics]

Come chaps. Kiss and make up. It's nearly Christmas.

[adamsclan]

Come chaps. Kiss and make up. It's nearly Christmas.

I'm doing my best! I'm happy to offer the olive branch in the hope of peace on earth, goodwill ....etc. I draw the line at the mistletoe though!

[scubapics]

Come chaps. Kiss and make up. It's nearly Christmas.

I'm doing my best! I'm happy to offer the olive branch in the hope of peace on earth, goodwill ....etc. I draw the line at the mistletoe though!

 

Indeed you are sir! Good on you. I wish I could help but the mods to your car are way above my station! Good luck!

[adamsclan]

Come chaps. Kiss and make up. It's nearly Christmas.

I'm doing my best! I'm happy to offer the olive branch in the hope of peace on earth, goodwill ....etc. I draw the line at the mistletoe though!

 

Indeed you are sir! Good on you. I wish I could help but the mods to your car are way above my station! Good luck!

Trouble is they're way above mine!!

[Dblock]

Just get shiply to pick up your car and they will take it to where ever you want for a good bit of money but then at least your car will work.

[adamsclan]

Just get shiply to pick up your car and they will take it to where ever you want for a good bit of money but then at least your car will work.

I had already been on to Shiply and received some reasonable quotes the cheapest being 20% of the £1,200 I was quoted by a local company - not sure whether that included 2 nights at the Aylesbury Sheraton!!

After some consideration, I am going to trailer it down on a trailer hired from McIntosh of Brechin - £39 per day. Given the nature of the fault(s) on the car I think it is best to talk face-to-face to try to explain all the various cut-outs/misfires/non-starts. The choice of company appears to be between DS Automotives in Aylesbury, the only APS dealer or Abbey Motorsport who seem to be very highly rated in various repairs/tune-ups on this forum. Have to get the de-mountable tow-bar on my X3 to work first though. Shame I can't use a more local company but there you go! Cheers

[Dblock]

Just get shiply to pick up your car and they will take it to where ever you want for a good bit of money but then at least your car will work.

I had already been on to Shiply and received some reasonable quotes the cheapest being 20% of the £1,200 I was quoted by a local company - not sure whether that included 2 nights at the Aylesbury Sheraton!!

After some consideration, I am going to trailer it down on a trailer hired from McIntosh of Brechin - £39 per day. Given the nature of the fault(s) on the car I think it is best to talk face-to-face to try to explain all the various cut-outs/misfires/non-starts. The choice of company appears to be between DS Automotives in Aylesbury, the only APS dealer or Abbey Motorsport who seem to be very highly rated in various repairs/tune-ups on this forum. Have to get the de-mountable tow-bar on my X3 to work first though. Shame I can't use a more local company but there you go! Cheers

 

Honestly if I was you take it to Abbey.

 

I know they arent cheap and stuff like that but trust me they will fix the car for you. Mark is always helpful and knows his stuff. I dont let many mechanics near my car as most are crap but I would leave him with the keys no problems. I do get that they are miles away but they WILL most likely fix it for you. There would be nothing worse than getting it 400miles away to another garage who doesnt know. Good luck with whatever you do mate

[adamsclan]

Just get shiply to pick up your car and they will take it to where ever you want for a good bit of money but then at least your car will work.

I had already been on to Shiply and received some reasonable quotes the cheapest being 20% of the £1,200 I was quoted by a local company - not sure whether that included 2 nights at the Aylesbury Sheraton!!

After some consideration, I am going to trailer it down on a trailer hired from McIntosh of Brechin - £39 per day. Given the nature of the fault(s) on the car I think it is best to talk face-to-face to try to explain all the various cut-outs/misfires/non-starts. The choice of company appears to be between DS Automotives in Aylesbury, the only APS dealer or Abbey Motorsport who seem to be very highly rated in various repairs/tune-ups on this forum. Have to get the de-mountable tow-bar on my X3 to work first though. Shame I can't use a more local company but there you go! Cheers

 

Honestly if I was you take it to Abbey.

 

I know they arent cheap and stuff like that but trust me they will fix the car for you. Mark is always helpful and knows his stuff. I dont let many mechanics near my car as most are crap but I would leave him with the keys no problems. I do get that they are miles away but they WILL most likely fix it for you. There would be nothing worse than getting it 400miles away to another garage who doesnt know. Good luck with whatever you do mate

Thanks for that. I'll give them a call Monday. You never know, they might be open. Hell of a trip this time of year! Cheers

[adamsclan]

http://s1308.beta.photobucket.com/user/the_dice_man/media/350Zpiggybackconnections_zps8c8b89c3.jpg.html?sort=3&o=0

 

Comments?

[ChrisS]

 

Bit of solder would not go amiss.

[Ekona]

Am I right in seeing two bare cables there? One yellow and one brown?

[adamsclan]

 

Bit of solder would not go amiss.

I cannot believe any "performance tuning" enterprise would turn this out as a professional finished product. Dave at DS Automotives discovered this mess after I trailered my car 450 miles to hopefully fix the misfire. I am kicking myself that I did not have the cohonies to investigate the ecu/piggyback set-up myself, but as I stated previously I'm not confident about the electronics side of cars especially with engine management systems. So - thank you WRC Tech who fitted the APS kit for a very poor wiring install. Don't get me wrong - the actual kit installation is faultless. No leaks, nothing interfering with any other components, no chafing cables or hoses. Why do such a crap job on this element of the install? How this lasted 6 years and 38k miles is amazing - perhaps super strength insulating tape! Keyser gets the winning prize of a £1 voucher to Top Girl as he suggested I examine the ecu/piggyback connections - so thanks for that. Just wish I'd done it. Ah well. Getting the whole car checked over to make sure all is well, the looking forward to my 450 mile trip back to Dundee. Bit of snow would be nice! Cheers.