Cold starting problems

The Oily Bits S1 Specific Topics
1

Hi guys,I’ve been having some trouble starting the car for the past few days. It’s turning over ok, but it just doesn’t seem to want to fire. Sometimes it’ll go on the second attempt, sometimes it just won’t. Strangely, it always starts easily later in the day. I guess it’s related to damp or temperature.I’ve replaced the battery, and the spark plugs (which were a bit damp and rusty), but this hasn’t helped.Please can anybody offer any ideas ?

2

Fuel pump? immobiliser ?

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Interesting ideas. I doubt it’s the immobiliser because the engine is turning over fine, and then it starts to fire on one cylinder, and slowly grumbles into life. Would the fuel pump cause this effect? I really have no clue.

4

Brendan, are you getting moisture into the plugs? I used to have this problem, until I used the Rob Gibbons Mk 2 conversion method.(cheers again Rob) [image]http://www.exiges.com/ubb/NonCGI/images/icons/grin.gif[/image]

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Hi Brendan,I’ve flown this one before but here goes…When you attempt to start do you disengage the clutch? The handbook recommends this and, theoretically at least, it should mean lower demands on the starting circuit if you don’t drag the gearbox around with the engine…BUTI have always found with a number of lotus cars, particularly the newer ones, that they seem to start better if you do not depress the clutch ( with the gearbox in neutral of course…). I have no logical or engineering explanation for this but I guess it must be something to do with electrical loads, oil drag and the like producing the best voltages for the starting cycle.Before you write me off as a complete nutter please try it… Of course, if you already are leaving the gearbox engaged then try it the other way and maybe disprove my theory…RegardsMike

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Brendan,Can you explain your full starting procedure, e.g. do you hear the fuel pump priming, does the immobiliser click when you press the button on the key, do you leave the throttle alone or depress it when cranking?Cheers

7

Hi guys, thanks for the replys.There shouldn’t be much moisture in the plug wells. I’ve got the MK2 cam cover shield. (I think I did it before Rob [image]http://www.exiges.com/ubb/NonCGI/images/icons/tongue.gif[/image])I don’t depress the clutch when starting.I switch the ignition on, and wait until I hear the fuel pump stop. Then I try starting the car without pressing the throttle.Only if it has failed to start a few times do I try pressing the throttle. (I believe pushing the throttle fully down should cut the fuel supply, and prevent flooding. Is this correct on modern cars?)A bit of extra background: Some of the things that have happened just before it all went wrong.1) The car had a 12000 mile service.2) The head was removed to re-shim the tappets.3) The ECU was reprogrammed (recall thing).4) I left the lights on all day, and killed the battery. (Somehow we managed to start a small fire when trying to jump start it [image]http://www.exiges.com/ubb/NonCGI/images/icons/shocked.gif[/image] but no damage was done)I guess any of these things could have contributed to the problem. Maybe.

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Well, nobody guessed it…It was the fuse for the ECU. It hadn’t entirely gone, but it was hanging by a thread. Sometimes it made contact, and sometime it didn’t.Thanks to Nick Whales for finding the fault.

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Nope would not have guessed that!!Nick Whales must have dislogded it when the ECU was reprogrammed [image]http://www.exiges.com/ubb/NonCGI/images/icons/shocked.gif[/image]

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Phil, the fuse wasn’t dislodged, it was sort of half-blown. The wire was broken, but the two halves of the wire inside the fuse were still barely touching! I don’t think I can blame Nick Whale’s for that.

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Ahhhh i see, if something like that happened after the car has been to a dealer, i would always blame them “it wasn’t like that when i bought it here” [image]http://www.exiges.com/ubb/NonCGI/images/icons/wink.gif[/image]

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Yeah, and I swear it had an ultra close ratio gearbox when I brought it in [image]http://www.exiges.com/ubb/NonCGI/images/icons/grin.gif[/image]

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[image]http://www.exiges.com/ubb/NonCGI/images/icons/grin.gif[/image] - and a new set of tyres [image]http://www.exiges.com/ubb/NonCGI/images/icons/wink.gif[/image]