Rich Posted February 14, 2014 Author Report Share Posted February 14, 2014 Interesting... so the car drives better/worse dependant on the air temperature. Could be a faulty sensor? It's looking that way. I mainly drive early morning or early evening when the temperature is around 3-5 degrees. Yesterday afternoon it was 8-10 degrees and should be similar today. I'm leaving work soon so will find out. If it is a sensor I'm not sure what it could be though, there is no MAF sensor but there is an intake air temperature (IAT) sensor. See item 14 on this diagram - http://www.lingshondaparts.com/honda_car_parts_selection_pfk.php?block_01=17SED01&block_02=B__0100&block_03=443 This is the throttle body - http://www.lingshondaparts.com/honda_car_parts_selection_pfk.php?block_01=17SED01&block_02=E__0101&block_03=443 Quote Link to comment Share on other sites More sharing options...
Steve-O Posted February 14, 2014 Report Share Posted February 14, 2014 Yeah so the IAT does record air temps - if thats giving off incorrect numbers that must have a negative effect on the way the engine is fuelled etc... You might be able to remove the sensor, clean with contact cleaner and refit, maybe run a multimeter over to check resistance. A new sensor is only £15 or something i think. I have one on the mx5 now which replaces the MAF. might explain why you dont have a MAF - you have one or the other? Quote Link to comment Share on other sites More sharing options...
Rich Posted February 14, 2014 Author Report Share Posted February 14, 2014 I did try removing it when I cleaned the throttle body but it's in there quite tight. I removed the clip around the rubber but I didn't want to pull too hard in case I damaged it. I had a similar problem with the Corolla feeling abit lumpy at low rpm (idle was ok) so replaced the MAF on that. The IAT was built in I think as the readings from it didn't seem correct but I had no CEL on that. Fitting another (used) MAF did seem to sort it out though. I might hook the laptop up and see what readings I get from it. A genuine sensor is around £50 I think, I can't find any on ebay though. I'll see if anyone is breaking a car I can get one from to try. Quote Link to comment Share on other sites More sharing options...
Steve-O Posted February 14, 2014 Report Share Posted February 14, 2014 might not be a bad place to look. Its what i would look at if i didnt want to throw money at it. Quote Link to comment Share on other sites More sharing options...
Steve-O Posted February 14, 2014 Report Share Posted February 14, 2014 look at euro car parts - they are having a sale on atm - you never know.. Quote Link to comment Share on other sites More sharing options...
Rich Posted February 26, 2014 Author Report Share Posted February 26, 2014 ECP don't sell the sensor, I'll try ebay for cars getting broken or one of these online breakers yard sites. I'm pretty sure this is sensor related, the car just doesn't feel as smooth as it should, as well as the bouncy revs. It's forecast for rain all day tomorrow but I need to get this oil change done and I want to do the spark plugs. I also need to check the rear suspension out, I have a knock coming from some as well as the front! Hopefully just another drop link so I'll replace all four and I might do the rear ARB bushes as well. Quote Link to comment Share on other sites More sharing options...
adam_r Posted February 26, 2014 Report Share Posted February 26, 2014 Rich.. dont touch the drop links until you have changed all the ARB bushes.... I made this mistake! Spent almost £100 for a set of good quality droplimks to find they didnt make squat all difference... spent a few quid on genuine rubber arb bushes and it solved my issue! Quote Link to comment Share on other sites More sharing options...
Rich Posted February 27, 2014 Author Report Share Posted February 27, 2014 Well the front ARB bushes seem fine, I can't get the bar to budge so will change those drop links. The rear seems fine as well, with the car on the ground I can't move any of the parts so I don't think the knocking is from that. What else could cause a knock on the rear when going over bumps, top mounts? I did the oil change today, the filter is in a better place than the Civic, just need to take the drivers wheel off to remove it. While I was under the car I noticed the condenser has rotted and there are alot of holes in it! The air con worked when I bought the car but I've a feeling it won't be now! I changed the spark plugs as well and one of them was loose! I went to undo it and there was no resistance at all, it wasn't even hand tight! These were the old ones (all 4 were the same), how do they look? Driving the car after fitting them was better, it felt smoother and not as lumpy as it has been but the real test will be in the morning going to work. I cleaned the IAT sensor but the revs were still bouncing although they didn't seem to be as often or dropping as quick as they were. Quote Link to comment Share on other sites More sharing options...
liner33 Posted February 28, 2014 Report Share Posted February 28, 2014 Hard to see from that pic, need to see the tip but they look like they've been in a while Quote Link to comment Share on other sites More sharing options...
Rich Posted February 28, 2014 Author Report Share Posted February 28, 2014 Hard to see from that pic, need to see the tip but they look like they've been in a while They've been in for 25k miles but the service interval is suppose to be 75k miles. I'll get the proper camera out and get a better photo. Driving it into work this morning it definitely feels better overall and I also re-adjusted the throttle cable as I think I did it too tight before. The car was getting to 5-10mph without me even touching the pedal! I've only done 10 miles so far but it doesn't seem to be dropping the revs as much from a higher speed. If I'm doing 20mph and the revs are around 1400rpm when I lift off they drop to idle speed and then back up again. It seemed to do it nearly every time this morning. The IAT sensor is encased in plastic as well, I was expecting to see an exposed wire so I don't think dirt could cause any issues, if it is this it would be the sensor itself. I don't know whether to try and get hold of another throttle body to swap them over cos I'm running out of ideas, I might have to take it to a garage to be looked at. Quote Link to comment Share on other sites More sharing options...
Steve-O Posted February 28, 2014 Report Share Posted February 28, 2014 I'd agree they dont look new. Normally i look for a golden brown where as on the face of it those look black which might indicate it could be running a bit better. Are they the correct grade? i.e not too cold? Check this out http://members.modernvespa.net/fabio_dougie/uploads/spark_plug_colour_810.jpg I would just run the plugs and see where they are come service time. That said i wouldnt personally use densos (NGK are my preference) but in your application you will be fine. Quote Link to comment Share on other sites More sharing options...
Rich Posted February 28, 2014 Author Report Share Posted February 28, 2014 Do those photos represent the iridium tipped plugs as well? I'll check them when I'm home but they didn't look as bad as any of those. Yes they're the correct ones, Honda recommend either these Denso ones or NGK. As long as it's working efficiently does it matter what brand you use? I used Denso's in the Corolla with no problems but the Civic has NGK ones. I just had an email from one of the online breakers for the sensor. They want £15 for the part and £8 postage!! It would only cost 2 quid to post FFS!! Quote Link to comment Share on other sites More sharing options...
adam_r Posted February 28, 2014 Report Share Posted February 28, 2014 rich.. you cant move the arb when the cars on the ground!!! just trust me, for the sake of a few quid and a few bolts give it a go. mine 'looked' fine but the rubber had gone hard ish and was allowing the arb to 'rattle' a very small amount enough to cause the knocking noise Quote Link to comment Share on other sites More sharing options...
Rich Posted February 28, 2014 Author Report Share Posted February 28, 2014 rich.. you cant move the arb when the cars on the ground!!! just trust me, for the sake of a few quid and a few bolts give it a go. mine 'looked' fine but the rubber had gone hard ish and was allowing the arb to 'rattle' a very small amount enough to cause the knocking noise The drop links you test with the car on the ground though? The front ones I am not doing yet cos you need to drop the subframe abit. I'll do the rear though, they're easy enough to get to. The cheapest I've seen them online is here - http://www.tegiwaimports.com/genuine-honda-03-07-accord-rear-anti-roll-bar-bushes-3816/ Anyone got a discount code for them, I'm not a member on any of the forums they're on? Although HH might do them postage free so could be cheaper from them anyway. Probably a good idea to get new clamps and bolts as well. My brake pedal is also spongy and I'm thinking of getting braided lines before changing the fluid but I've never used them before, do they make that much difference? Quote Link to comment Share on other sites More sharing options...
adam_r Posted February 28, 2014 Report Share Posted February 28, 2014 I hate to correct you again Rich. but you cant check the accords arbs with the wheels on the ground... they are under load and wont rattle Quote Link to comment Share on other sites More sharing options...
Rich Posted March 1, 2014 Author Report Share Posted March 1, 2014 I hate to correct you again Rich. but you cant check the accords arbs with the wheels on the ground... they are under load and wont rattle You can't check any anti roll bar with the weight of the car on it that would be obvious. I'm talking about the drop links and on the rear there is no movement from them at all but on the front one of them has play in it. I've not jacked the car up at the rear yet to check the bushes but it's a quick and cheap job to change them so might do these anyway. Quote Link to comment Share on other sites More sharing options...
Rich Posted March 1, 2014 Author Report Share Posted March 1, 2014 Things aren't getting better, it seems to have got worse after a longer drive today. When I accelerate and then lift off the rev counter drops to as low as 650rpm, even when I'm doing 50mph (it wasn't doing it over 40mph before) and then goes back up again. Sometimes it can be ok for a while when I lift off but as soon as I brake and start slowing down it does the same thing. The car seems to be driving fine though and changes gear accordingly when I change over to semi auto to check the gear number in the display, the revs certainly don't match the engine speed. Does this sound like it's the IAT sensor as it's got worse after cleaning that or could something else be causing it? When the car is idling in P, N or D I don't have this problem at all, would a faulty IAT sensor cause idle issues as well? The revs stay at 650rpm and may increase slightly if I use any of the elctrics, it's only doing it when I'm driving. Adding another thought, cos the car is drive by wire there is a throttle position sensor on the accelerator cable. As this seems to be happening when I lift off the throttle I'm wondering if this could be faulty? To top it all off I noticed one of the rear brakes is hot and smells abit so looks like that is starting to bind! Quote Link to comment Share on other sites More sharing options...
Steve-O Posted March 1, 2014 Report Share Posted March 1, 2014 I think an hour of proper diagnostics at this stage might save you a load of a grief and wasted money on playing the swap parts game mate. Only constructive thing I can add is might be something related to the vacuum so check along those lines. Quote Link to comment Share on other sites More sharing options...
liner33 Posted March 1, 2014 Report Share Posted March 1, 2014 Accelerator cable AND drive by wire? Doesn't sound like iat to me have you got any fault codes on it ? Quote Link to comment Share on other sites More sharing options...
NickT Posted March 2, 2014 Report Share Posted March 2, 2014 Have you had the codes read on the car? With the issue of the spark plug now sorted out snd running a bit better, I wonder if the ecu needs reseting to default self learn values. (Usually disconnect the battery for at least 3 hours). Obviously make sure you have the codes for the radio and any procedure for re synchronising your door keys. .. Quote Link to comment Share on other sites More sharing options...
Rich Posted March 2, 2014 Author Report Share Posted March 2, 2014 Accelerator cable AND drive by wire? Doesn't sound like iat to me have you got any fault codes on it ? No faults code and none stored so that doesn't help. It has a cable from the pedal to the throttle position sensor. There is another sensor on the throttle body that opens the butterfly when the pedal is pressed. I did some reading on the TPS yesterday and went out for a drive to test it some more, I'm almost certain it's this sensor. At idle it's fine. When accelerating it is fine. When lifting off the rpms drop to 650 and then go back up. If I don't accelerate again it's fine. If I put pressure on the pedal so the car holds the speed/accelerates slightly the rpms don't drop. As soon as I lift back off, lift off completely whether to brake or not they drop. If I use cruise control the rpms don't drop at all. The sensor is item number 2 - http://www.lingshondaparts.com/honda_car_parts_selection_pfk.php?block_01=17SED01&block_02=B__2316&block_03=443 I unbolted it so I could try to clean it but it's riveted on! I cleaned and sprayed the electrical connectors instead, which hasn't really made any difference. I'm positive this isn't a vacuum leak cos the revs should increase as well, not just decrease, plus I would probably have issues when idling and the car may surge? There don't seem to be that many threads on the UK Accord with these failing, the few I have found suggest that cleaning it worked, which I've already tried. There is this thread on a US forum and the TPS has the same part number as mine - http://tl.acurazine.com/forums/showthread.php?t=726039 I know I really need to get it diagnosed properly but I can't see what else it can be, it's all linked to the throttle pedal. The sensor is £210 from Honda so I wouldn't get that unless I definitely knew it was this. I went for a drive earlier with the laptop plugged in but it couldn't measure the TPS just the throttle position in relation to the speed. I didn't reset the ECU after changing the plugs, I guess it's worth a try. Quote Link to comment Share on other sites More sharing options...
NickT Posted March 2, 2014 Report Share Posted March 2, 2014 I know this may seem "old skool" bit have you tried using an oscilloscope to look at the signal from the throttle position sensor to see if it is smooth when your foot presses the accelerator slowly? You could try disconnecting it and see if the car drives better. I'd try the reset first and take it from there Quote Link to comment Share on other sites More sharing options...
Rich Posted March 3, 2014 Author Report Share Posted March 3, 2014 No I've not tried that yet but will be doing so on Thursday when I'm off work. I have found a good guide to use here - http://www.enduringautomotive.com/tps/ I am assuming the throttle butterfly will open with just the ignition on, I don't need the engine running? I'll test the TPS first and then the sensor on the TB and see what that is reading, I'd imagine it's the same procedure for both sensors. I might actually remove the TB this time and give it a thorough clean. If that still doesn't help I'll have to book it in somewhere Quote Link to comment Share on other sites More sharing options...
Rich Posted March 4, 2014 Author Report Share Posted March 4, 2014 Just come across an interesting thread about cleaning the TB on these cars, although the issues I have started before I even touched it. I could possibly have made things worse by cleaning the TB? http://www.pakwheels.com/forums/performance-modification-tune-up-preventive-maintenance/180157-attention-8th-generation-civic-3rd-generation-city-accord-owners-dbw-related Quote Link to comment Share on other sites More sharing options...
liner33 Posted March 4, 2014 Report Share Posted March 4, 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 Quote Link to comment Share on other sites More sharing options...
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