Rich Posted March 5, 2014 Author Report Share Posted March 5, 2014 Its not unheard of to damage the TB cleaning it , I still dont think its anything to do with the sensor , sounds like fuelling to me Fuelling? I would have thought the car will stall if it's getting starved of fuel. I'll test the sensors tomorrow and maybe clean the TB again but I'm abit concerned I might make things worse if I remove it to clean? I'll have to book it in someone to be diagnosed properly if I can't figure it out. This is why I avoided modern cars for so long, too much is controlled by computers now, which the home mechanic needs specialist equipment to fault find! Quote Link to comment Share on other sites More sharing options...
liner33 Posted March 5, 2014 Report Share Posted March 5, 2014 Overfuelling on idle , when you shut the throttle the problem becomes worse until the system compensates , closing the throttle more slowly allows the system time to control the fuelling better Quote Link to comment Share on other sites More sharing options...
Rich Posted March 5, 2014 Author Report Share Posted March 5, 2014 Overfuelling on idle , when you shut the throttle the problem becomes worse until the system compensates , closing the throttle more slowly allows the system time to control the fuelling better So how could I check something like that myself? Quote Link to comment Share on other sites More sharing options...
liner33 Posted March 5, 2014 Report Share Posted March 5, 2014 you could check the voltage from the lambda , do you have a obd reader or android phone? Quote Link to comment Share on other sites More sharing options...
Rich Posted March 5, 2014 Author Report Share Posted March 5, 2014 you could check the voltage from the lambda , do you have a obd reader or android phone? I have an OBDII reader I use with my laptop, so I'll check the voltages of those. Does the car need to be running to check those or just the ignition on, I can't remember? Quote Link to comment Share on other sites More sharing options...
liner33 Posted March 5, 2014 Report Share Posted March 5, 2014 yes run a live log and see what the lambda is doing Quote Link to comment Share on other sites More sharing options...
Rich Posted March 5, 2014 Author Report Share Posted March 5, 2014 Ok I'll go for a run in the morning and log some data. I want to back probe the TPS sensor and the guide I found is for a 3 pin connector. Mine has 5 so is it just trial and error to fine the correct wire, can I damage anything if I pick the wrong one? Quote Link to comment Share on other sites More sharing options...
Rich Posted March 5, 2014 Author Report Share Posted March 5, 2014 Got another symptom now, gear change has become noticeable and feels notchy. It was seemless before, you couldn't feel it. I'm definitely convinced it's the TPS or TB, this is also a symptom of it being defective. Quote Link to comment Share on other sites More sharing options...
parthiban Posted March 6, 2014 Report Share Posted March 6, 2014 Got another symptom now, gear change has become noticeable and feels notchy. It was seemless before, you couldn't feel it. I'm definitely convinced it's the TPS or TB, this is also a symptom of it being defective. When was the gearbox oil last changed? Quote Link to comment Share on other sites More sharing options...
NickT Posted March 6, 2014 Report Share Posted March 6, 2014 Wheeler dealers porsche episode Quote Link to comment Share on other sites More sharing options...
liner33 Posted March 6, 2014 Report Share Posted March 6, 2014 9 times out of 10 gearbox problems are due to low or old oil , that 1 time though can be very expensive Quote Link to comment Share on other sites More sharing options...
Rich Posted March 6, 2014 Author Report Share Posted March 6, 2014 It's been better today, I think the gearbox is related to the rpm issue, I've read it can affect the smoothness of the gear change. The oil was replaced 25k miles ago and is due every 50k miles or 4 years. It's been 4 years now so is due a change and is the next job on my list once I've ordered the oil. I'll do the Civic at the same time cos that is due as well. I'm meeting the guy who owns Premier Tuning in half an hour, it just so happens he's staying in Watford this week! He's going to do a diagnosis and recalibrate the sensors for me using his HDS. Hopefully I will at least find out what is causing the problem if he can't fix it now. 1 Quote Link to comment Share on other sites More sharing options...
Rich Posted March 7, 2014 Author Report Share Posted March 7, 2014 It was an interesting meet last night. When I left home the CEL came on, first time it has happened! He used the HDS system to read the codes and it was Accelerator Pedal Position sensor voltage low A and B. I have been calling the APP the TPS, I was wrong, this is actually in the TB, which he tested and it's fine. So everything I've been talking about is actually the APP sensor. The voltage on the APP sensor when I pressed the pedal was between 0.45 and 4.5 and was within range. These voltages are classed as A, the B reading is half of the A voltage. We forgot to check closely to see if it was spiking but I don't think it was. It looks like it's either the sensor or the wiring that is at fault. There were some other codes as well that my OBDII reader couldn't see, they were for the battery problems I had when I got the car and the auto wipers, but these work fine. Cleared all the codes and I still have the problem but the CEL hasn't come back on. Cheapest APP sensor I've found so far is £50 but I don't want to spend too much in case that isn't the problem. They don't really fail so aren't a popular part to sell, which should help me get one cheap enough. Quote Link to comment Share on other sites More sharing options...
parthiban Posted March 7, 2014 Report Share Posted March 7, 2014 Doesn't sound like it's the APP sensor then - did he take the car out for a test drive? What did he think of the symptoms? Quote Link to comment Share on other sites More sharing options...
Rich Posted March 7, 2014 Author Report Share Posted March 7, 2014 Doesn't sound like it's the APP sensor then - did he take the car out for a test drive? What did he think of the symptoms? No he didn't take it for a drive but we couldn't of anyway, the traffic was too heavy as we were parked at a hotel on the A41 - it was gridlocked! He's down this way every week working, although lives up North and he'll do more tests if needed. He said he's more of a tuner and does remaps, removes DPF etc and so I don't think he really fault finds. This is only a side job for him as well, not his main job. The code was for the sensor though, it could be temperamental but the only way I'll know is if I get hold of one to swap it over. Cheapest price I've been given so far is £50, the most was £130 but I don't want to pay that much. It's rare for these to fail and if it turns out to be ok I'll be stuck with something I can't sell on and out of pocket! It could be a short in the wiring, which means I'll need an auto electrician to test it out. The voltages seem to indicate it's ok, but the sensor could be misinterpreting these. I can't remove the sensor but am going to try cleaning the whole thing. I have some GT85, which says it's ok for electrical components. Is this stuff the same as proper contact spray, anyone know? Quote Link to comment Share on other sites More sharing options...
parthiban Posted March 7, 2014 Report Share Posted March 7, 2014 It could be worth checking with a dealer on this now, and say it's reading this code but is that likely to be the issue? They might even agree to change it on the basis it fixes the fault, and if it doesn't to give you a refund (if they're a good one). Quote Link to comment Share on other sites More sharing options...
Rich Posted March 7, 2014 Author Report Share Posted March 7, 2014 The CEL is off now and the codes have been wiped so I'd imagine they will want to run a diagnosis themselves first, which is how much? The part new is £210 so I'd be better off buying a used one cheaply first. I'll change the gearbox oil, try to get hold of a sensor and then go from there! Quote Link to comment Share on other sites More sharing options...
parthiban Posted March 7, 2014 Report Share Posted March 7, 2014 The CEL is off now and the codes have been wiped so I'd imagine they will want to run a diagnosis themselves first, which is how much? The part new is £210 so I'd be better off buying a used one cheaply first. I'll change the gearbox oil, try to get hold of a sensor and then go from there! Ouch, ok yep that sounds a better plan Quote Link to comment Share on other sites More sharing options...
Steve-O Posted March 8, 2014 Report Share Posted March 8, 2014 I would bank on an hours labour at least for a diagnostic session - which could be £50-£100 at honda and thats just to tell you whats wrong. As i said before though - that might be money well spent in the long run. The S3 had a CEL light on when i bought it but i knew it wasn't a terminal issue. That said i still had it checked on a Audi/VW machine by a master technician - they have practical experience beyond what an error code tells you that might cut to the chase instead of going round the houses. The car has been sweet as a nut ever since - no lights on dash. Quote Link to comment Share on other sites More sharing options...
Rich Posted March 10, 2014 Author Report Share Posted March 10, 2014 It's not been as bad over the weekend still doing it but not as often. I took the Civic out as well and paid attention to the rev counter this time, I was surprise to find it was doing the same thing but no where near as bad as the Accord. I accelerated, released the pedal and the rpms drop slowly, dip abit more (close to idle rpm) and then rise back up again. My car just seems to have started doing it more aggressively and I'm wondering if it's actually a characteristic of an automatic gearbox? My gearbox oil should be here today so I'm hoping to get that changed on Thursday so we'll see what happens. If that doesn't help I'll get a used APP sensor and if it still doesn't work I'll book it in but there are no codes on the ECU at all, they've all been cleared and haven't come back on. The only other thing I thought of was the gearbox sensor but I don't think that would cause this issue? Quote Link to comment Share on other sites More sharing options...
SMARTLY Posted March 10, 2014 Report Share Posted March 10, 2014 Old school engines always used to drop the revs when you take the foot off the gas, often referred to as engine braking. I was quite surprised when my first new school was still doing 3000 revs with foot off the gas. Quote Link to comment Share on other sites More sharing options...
Rich Posted March 10, 2014 Author Report Share Posted March 10, 2014 Autos don't have engine braking though? Yes the rpms drop but shouldn't do it as quickly as what the Accord is and not down to idle speed. I need to take a video of what it is doing but don't have a mount for the phone or camera. Quote Link to comment Share on other sites More sharing options...
parthiban Posted March 10, 2014 Report Share Posted March 10, 2014 When you say engine revs drop, how exactly is it doing it? For example if you lock the car in second gear, and drive along at a constant throttle pressure and revs and then let go of the accelerator, do the revs just drop to idle? What do you mean when you say autos don't have engine braking? Quote Link to comment Share on other sites More sharing options...
Rich Posted March 10, 2014 Author Report Share Posted March 10, 2014 When you say engine revs drop, how exactly is it doing it? For example if you lock the car in second gear, and drive along at a constant throttle pressure and revs and then let go of the accelerator, do the revs just drop to idle? What do you mean when you say autos don't have engine braking? Yes I've done that test with 2nd gear and they drop then rise again to where they should be. Autos don't have engine braking or maybe just a little. When you let go of the accelerator pedal in a manual the speed with start dropping instantly, in an auto it doesn't. Quote Link to comment Share on other sites More sharing options...
parthiban Posted March 10, 2014 Report Share Posted March 10, 2014 Yes I've done that test with 2nd gear and they drop then rise again to where they should be. Autos don't have engine braking or maybe just a little. When you let go of the accelerator pedal in a manual the speed with start dropping instantly, in an auto it doesn't. Doesn't really sound right - it's almost as though the engine and gearbox are disengaging briefly? Engine braking just depends on what gear you're in surely, if you stay in 6th in a manual and lift off the engine braking effect will be the same as in an auto in 6th gear. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.