Idle problems-1.6 auto

[Wonko_The_Sane]

I've had a problem the last week with H870. When starting etc from cold, it's fine. While driving, it's very sprightly indeed. Once warmed up, it's fine. Enter a junction into the equation, and it's..not.

Regardless of warmed up fully or not, H870 has started to die at the FIRST junction of the day. It'll be driving just fine, but if I pull up at any given junction, the engine slows, staggers around the 4-500rpm mark, and more often than not dies. It won't settle with a quick rev either.

The odd thing is that once it dies, if I cycle the ignition and restart it now it's warm, it sits and idles at 850RPM quite happily.

As I say, it happens regardless of the distance driven from cold before the actual junction..it's as if the ECU, having got the engine from cold has "miscalculated" something and needs to be reinitialised to "learn" how to handle the engine in it's warmed up state.

Anyone got any ideas? It's usually a 1-off operation per cold journey..but 2 foot auto driving, to stop a stall gets a bit wearing..:)

(It's a '91 S Series, Unleaded, Manual Choke, No ORFCO Valve connected at this time, recently had a total distributor cap/rotor arm/lead/plug clean)

[Maria]

Mine went through a stage some time ago of randomly dying at traffic lights, and then being fine after a switch-off and on again, and I do seem to remember the fuel ECU being at fault.

[MGTurbo]

Can't see the fuel ECU being a problem, its a manual choke, and with the fuel-cut off valve disconnected, makes it completely independant of any ECU control. My 1.6 Auto was equally as temprimental, the areas i would look in would be, float chamber level, fuel pump, fuel filter. And if you can find a late 1.6 carb from a Montego swop the auto linkage over and do away with the fuel cut off completely to rule it out, could be opening by itself, you never know.....

Gareth

[G Force]

Hi there, some other things on my checklist would be check that the warm air intake is all functioning correctly and complete. check manifold heater is working as it should be. check vacuum switch diaphragm is ok. is the engine thermostat ok and not sticking open? it would normally take approx 4 miles to warm engine and auto box up to temp, pulling up before this in this cold weather may need a bit of fast idle from your manual choke.

you might of expected to have the later (eric) fuel/ignition on a 1991 car but i expect yours was one of the last pre 89 1/2 my to be sold.

cheers gary :)