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For the record, mine’s a 1988 Maestro EFI, but I expect all injection models will be the same.
Just thought I would post this in case anyone else ever has trouble like this.
The problem I had was the car would cut out and die after idling for an extended period, especially in hot weather. Generally the car would start and run again after key-off and restart, but sometimes would need a good bootful of throttle to recover. Anyway it made traffic queues a bit stressful.
Basically I was playing parts darts for a while, changing components and hoping I could cure it that way, but it kept happening. I finally decided to check the fuel pressure which required a gauge which I didn’t own, luckily a friend lent me his.
I tapped into the fuel feed after the filter using a T-piece and small length of pipe (8mm-ish ID). This allowed me to check the fuel pressure while the car was running.
Doing my ‘extended idle’ test after about 5 min at running temperature I could see the fuel pressure drop from a steady 2.1bar down to near zero, and with it the idle speed dropped, then the engine eventually died. So fuel pressure regulator was prime suspect – it is old and original to the car, contains some rubber parts and may have suffered with using E5 fuel rather than good old four star.
@jeff_turbo was kind enough to supply me with a used spare, which I fitted, then tested on the car.
Unfortunately I had an unrelated issue where the throttle potentiometer connector was making a bad connection, and until I fixed this I couldn’t get the car to rev much above idle speed. Once I’d cleaned the throttle body connector and refitted, car revved fine so I let it get to temperature and ran another test. Success! No dying after a period of idle.
A harsher test came when my son and I drove into Santa Pod to watch some drag racing on the hottest day of the year. The queues to get in aren’t too bad but there’s still a good ten minutes being stationary or near walking pace until you can park up. Again, passed with flying colours, no misbehaving.
Like a lot of EFI parts the fuel pressure regulator is NLA, but I found a possible alternative listed for Volvo 240 among others. It doesn’t have a threaded outlet like the Maestro one but in most other respects is identical. It should be possible to attach the rubber return hose directly to the FPR outlet, instead of using that weird bent pipe that runs over the throttle body (I still don’t know why that’s there).
Regarding the throttle pot connector, I’m tempted to replace this entirely with a new connector, something like those waterproof black sealed connectors they sell on eBay. There’s only 3 or 4 wires so it wouldn’t be a hard job. I am suspicious of the original Lucas connector as I think the pins are aluminium so less reliable than copper in my opinion.
Just thought I would post this in case anyone else ever has trouble like this.
The problem I had was the car would cut out and die after idling for an extended period, especially in hot weather. Generally the car would start and run again after key-off and restart, but sometimes would need a good bootful of throttle to recover. Anyway it made traffic queues a bit stressful.
Basically I was playing parts darts for a while, changing components and hoping I could cure it that way, but it kept happening. I finally decided to check the fuel pressure which required a gauge which I didn’t own, luckily a friend lent me his.
I tapped into the fuel feed after the filter using a T-piece and small length of pipe (8mm-ish ID). This allowed me to check the fuel pressure while the car was running.
Doing my ‘extended idle’ test after about 5 min at running temperature I could see the fuel pressure drop from a steady 2.1bar down to near zero, and with it the idle speed dropped, then the engine eventually died. So fuel pressure regulator was prime suspect – it is old and original to the car, contains some rubber parts and may have suffered with using E5 fuel rather than good old four star.
@jeff_turbo was kind enough to supply me with a used spare, which I fitted, then tested on the car.
Unfortunately I had an unrelated issue where the throttle potentiometer connector was making a bad connection, and until I fixed this I couldn’t get the car to rev much above idle speed. Once I’d cleaned the throttle body connector and refitted, car revved fine so I let it get to temperature and ran another test. Success! No dying after a period of idle.
A harsher test came when my son and I drove into Santa Pod to watch some drag racing on the hottest day of the year. The queues to get in aren’t too bad but there’s still a good ten minutes being stationary or near walking pace until you can park up. Again, passed with flying colours, no misbehaving.
Like a lot of EFI parts the fuel pressure regulator is NLA, but I found a possible alternative listed for Volvo 240 among others. It doesn’t have a threaded outlet like the Maestro one but in most other respects is identical. It should be possible to attach the rubber return hose directly to the FPR outlet, instead of using that weird bent pipe that runs over the throttle body (I still don’t know why that’s there).
Regarding the throttle pot connector, I’m tempted to replace this entirely with a new connector, something like those waterproof black sealed connectors they sell on eBay. There’s only 3 or 4 wires so it wouldn’t be a hard job. I am suspicious of the original Lucas connector as I think the pins are aluminium so less reliable than copper in my opinion.
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