Bully9

It's been happening for a while since a recent service, although i've driven the car very little since. And the service included a valve adjustment, although it may well be nothing to do with the problem. It's always been a bit lumpy at low revs, making smooth driving at low speed near impossible - in fact it's the one thing about the car i really dislike, and it seems to be a 'feature' that many have complained about, but to which i've never found a solution.

Anyway, the tickover when warm has become very erratic recently, fluctuating between 400 (almost stalling) and 1000 compared to 1000-1200 before. So i did some research and cleaned the map sensor and IAC valve with carb cleaner and (yet again) remapped the ecu (if that's the right phrase). It hasn't made a jot of difference.

Any constructive suggestions? Thanks.

flybikeslee

what filter are you using?

tozerman

Remove throttle body and clean thoroughly with carb/brake cleaner, make sure all the little holes and channels are clean etc, refit with new gasket and problem solved, text book problem, good luck

Bully9

Thanks for the replies.

flybikeslee - do you mean 'what air filter'? Just standard - about 3 months old.

tozerman - i saw a thread on TB cleaning so i tried the squirting cleaner down the tiny rear facing hole in the well below the map sensor. It was awkward and didn't seem as if it was doing anything, but i didn't take off the throttle body as i was not sure how to. I guess i'll have to get a gasket and give it a go. Thanks. Anything to watch out for? Do i need to do another ECU reset afterwards?

MB

It can be far more things than cleaning the TB.

There's an FAQ in the UK forum you should look through.

BenRNBP

Yeah I don't think this is the normal "clean the bits and reset ECU" issue either - worth checking the breathers, cam sensors and anything else that may have been disturbed when removing the cam cover for the valve clearance adjustment

Scottland

Make sure the ECU was reset properly and left long enough to 'learn' to idle properly. When I had mine done, we did an ECU reset but it didn't take properly. I think I ended up disconnecting the battery in the end to reset it.

Theheff

And see if the plug on the map sensor is on properly. I cleaned all of mine, eg valve throttle body, sensors etc and all was fine. Then it came back. Turns out it was as simple as putting a cable tie around the plug and socket to hold them together properly. It had been ok after the clean as I'd unplugged it and pushed it back on again. Obviously worked loose a little.

Bully9

Thanks for all the advice. Reading this and the FAQ it does seem there are a great many diverse possible causes. I know the service manager at Yeomans Churt where the valve clearances were done, and he has offered to pick the car up and take it for inspection/diagnosis. I think that might be the way forward rather than further DIY piecemeal attempts by myself. I'll update the thread next week if there is anything of interest to report.

Bully9

The honda mechanic had a look at this today and seems to think the culprit is the timing chain tensioner which is apparently a little noisy. The car is over 10 years old, but has only done 25k miles. If i do have it replaced, they are happy to charge an extremely reasonable £30 labour, but the part is getting on for £300 including VAT, which seems crazy. I've done a bit of research. Some have said that sandblasting the worm drive can fix a noisy tensioner, and i've also seen the part 14510-PCX-005 advertised on several US sites - including amazon - for around $120 + shipping. Not sure if they will ship to UK. Anyway, i'd welcome any words of advice.