[Alasdair Barron]

Dear Folks
I'm a newbie, and this my first time post.
Please bear with me and advise me if needed so I don't waste anyone's time.
---------------
Car - Mk 1 CRV Automatic, 2001, full UK spec, 95,000 miles.

Issue - stalls on cold start.

Description - starts first time every time, but as soon as lever moved from Park to Reverse, revs drop immediately, through Neutral - revs recover, and into Forward revs drop so low that it can stall.
Then I have to return to Park and restart, have to rev the engine to get it to the point where I can try again. Used to only do this in winter. I have just replaced the 'fast idle control valve' (see attached diagram, in yellow) and very disappointingly still have the same problem.
Once engine warm, no problems.

Notes
No other engine problems, runs fine at all speeds and loads.
Plugs always replaced regularly, currently less than 500 miles.
Battery about 18 months old.
Have put fuel injector cleaner through, no effect.
Tappets clearance set at recommended adjustment.
'Check engine light' does not come on.

1? - this engine type has a reputation for valve seat wear - but as tickover smooth unlikely.
2? - I will replace the air filter but don't expect that's the problem - though in combination with 1? it just might be.
3? - what is the reason why the 'fast idle control valve' doesn't seem to work.

Any suggestions would be appreciated.

Many thanks indeed.
Regards, A

 

[Lochinvar]

Easiest things first, have you cleaned your throttle body in the last 30k? If there's to much carbon build up, it will prevent the engine from getting enough air, and it will stall.

Next, some of the earlier CR-Vs have an idle adjustment screw on the top of the throttle. There's a procedure to adjust it. If that's not set correctly, it could be your problem.

There's also a Thermo valve on the bottom of the throttle body that increases the idle speed when the engine coolant is cold. That could also be your problem.

I would also check the transmission fluid, because it would stall the engine if the torque converter is partially locking up when it should be unlocked.

 

[Alasdair Barron]

Lochinvar - thanks for your very helpful reply.
Suspect thermo valve. I have booked the car in with a new garage next week, and will let you know the result.
Many thanks, A

 

[Alasdair Barron]

Here's the result/answer - as promised!
Lochinvar was right, cold start stalling was largely due to a dirty throttle body - which had not been cleaned, ever, ie in 97,000 miles.
The first garage I took the car to used three different kind of sprays to clean the throttle body (one at least not available to the public) and that solved the problem, plus cleaning the distributor - however I was not completely happy as the engine seemed to run a bit rough.
So I had a second garage take the throttle body apart and clean it properly - they reported that the previous cleaning (by spraying) had not been thorough.
However then the engine started to hunt - which was caused by a faulty Engine Coolant Temperature (2 pin) Sensor (ECT) - I replaced it and all is now fine. (Hunting was present to a small degree previously).
I did trust my servicing to be done well by Honda garages, and it was not, = disappointment.
Thanks Lochinvar for taking the time to write.
A