Engine Starts But Dies Instantly Intermittently

[saucy_begger]

car specifications : vauxhall cavalier OHC 1.8i LS single point injection hatchback M Reg

hi, I've been on here a wile and had a few problems but I'm happy to say my cav is running fine since the last time i wrote about a problem.... altho


i took my much loved cav to the garage yesterday to have new disks and pads as my pads had gone hard and was eating my disks and squealing in the process..
had her in only 5 Min's when the guy called me over to show me my wish bone bushes were totally gone and my wishbone was wobbling all over the place..
that will explain the play in my steering wheel and the speed wobble :L £230 and 2 hours later she is driving great and feels very smooth now bear in mind 230 is the most ive ever spent on this cav in 3 years of owning her and she only cost 500 when i bought her.

i have had a miner problem with her for a few months now tho about 7 to be exact. just sometimes and i mean like once or twice a month when she is stone cold and left for 2 days or hot from a good run i will go to start her and she starts and sounds like she has started but then dies instantly with the engine management light coming on at same time. ill turn the key to off then try again but this time she tries to start but sounds REALLY groggy like shes starved of fuel and the only way i can keep her running is to rev her every couple of seconds till the groggy sound slowly fades and she holds stable. after that she holds firm and sounds fine. she runs great no problems what so ever. i have changed the started relay, fuel filter, air filter and had a garage check the fuel pump. I'm out of ideas. it is really bothering me as i just spent 230 on her and I'm praying its not gonna get worse so i one day wont be able to start her it has fitted a vauxhall alarm with 2 fobs one fob on each key under the bonnet it has a square horn with a vauxhall griffin in the middle i think its standard as the key fob locks and unlocks the doors. no immobiliser as far as i know just dead lock and alarm. the engine is good n solid and no leaks or problems i know of. my battery is crap and needs charging a lot by not playing music and letting the alt do its job as i have a very power draining stereo(amps and subs). i have a power cap with a voltage readout and it shows 12.33v when the car is off and 14.2v or so when running.

p.s i love everything about this car and dont want to lose her but i can have a unreliable car so she needs fixing but i dont know where to start thanks for anyone that knows anything about this problem.

[Cavalier342]

Might just be your ICV that needs cleaning or replacing. That's located under the big GM black plastic air distributor cover. Small black unit, with a wired plug attached to it, it's held on by 2 small torx bolts. I'd look at this as a starting point. Be careful when removing the bolts, not to drop them behind the engine block, I've lost one before doing that. Other suggestion would be fuel pump, either way, do the paper-clip test to diagnose the problem.
Andrei.

[saucy_begger]

hi, sorry but whats the paperclip test?? i thought it mite be my idle valve because sometimes when started she idles a bit rough and tries to die till the engine revs a little then she will idle like wo wo wo wo the try to die again till the engine revs again then she holds stable. i only drive off once she is stable. someone told me its a costly job buying and fitting a idle valve on my car and its hard to get to on my engine. i'm sure they said at a garage its inside my engine? that is why i haven't had a new one fitted. is this true? if you guys think and are pretty sure its my idle valve ill get her in for a new one asap. but price is an issue as shes cost me alot this week already worth it tho

[Gaz]

id be changing = the coolant temp sensor and checking wiring - its the blue 2 pin connector, sounds like the sensor is on its last legs or there is a loose connection. If it was the icv it would play hell all the time not just when its cold.

[Robsey]

If it is a bit hit and miss when cold, this points to the coolant temperature sensor at the back of the engine next to the timing belt cover.

It is a blue rectangular bodied unit with a two pin connector.. If you have no engine light, then this would be the most likely culprit.

It may be causng your plugs to soot up due to an over-rich mixture.

If you have an engine light, then I would think of it possibly being the Oxy sensor (poor hot starting).
I had hot starting problems after a good run, due to the car running too rich.
plugs were getting really sooted up.

A good clean of the plugs soon returned the car to perfect running. Until it got sooted up again.


If there is an engine light on the dash, then you can do the paper-clip test.
If there is no light, then there is not much point as any faults displayed will be historic.

Paper clip test as it's name implies, is

Unplug the diagnostic plug under the bonnet at the rear.

Use a paper clip to short pin a to b (letters are printed into the plug body).
Turn on the ignition (engine not running),

and you should get the engine light flashing a sequence

it will start

1 - 2, 1 - 2, 1- 2 (this is just the test start up sequence).

if you get nothing but 1 - 2 after that, then no faults are stored.

any faults will be displayed 3 times... (the following are examples only)

such as 3 - 1, 3 - 1, 3 - 1... which would represent No RPM signal or

1 - 3, 1- 3, 1- 3 which represents a sluggish oxygen sensor

keep reading the codes, until you get 1 - 2 again, as this signifies that you have gone back to the start again.

[Squig]

Paperclip test and EML codes...

This should be the first port of call... it will at least give you an idea of what's wrong but Gaz is probably right

[saucy_begger]

hi, i'm going to get my clutch and cable and pedal checked out for free early next week so i'm just going to get my coolant temp sensor changed wile its in as its cheap and the last thing to replace as I've changed my fuel filter, fuel pump relay and air filter. the sensor was the last thing on the list so that's next. my car is constantly running rich to the point you can smell petrol out the exhaust and she uses a lot of fuel too. its costs £20 a week to get to work with trips to the shops and town runs as well. i work 5 miles away from work so ten there and back. i'm getting 100miles from £20 and a lot of people are saying that's really bad. i said to the garage today oh i want my coolant temp sensor changed wile i'm there n he said why? and i said because my car is running rich and not starting the odd time and he said ahh its nothing to do with that mate the sensor wouldn't not make your car start. i was like well its not the first time someone has said instantly change the coolant sensor when i told them my problem. apparently it was a real common fault on the model i have. a few garages have said that so with you guys saying it too shes getting a new one fitted end of thanks for all your time and help guys!! very grateful!!

[snowy]

Just make sure they change the coolant sensor for the engine management system not the one for the gauge!!

[saucy_begger]

hi, car is booked in for a clutch, cable and pedle box check next tue. hopefully i wont have any problems there, maybe a cable replaced but thats all im hoping needs doing but im going to say i want my coolant sensor changing and my oxygen sensor as the only time she wont start up is after a good long run and i know she is running rich as all you can smell is petrol from the exhaust and the engine smells hot like she is too hot and some people have commented about that before but i cant stress enough she has never overheated or gone over 92 degrees in the 3 years nearly that ive owned her. im feeling good about what you guys have said could be the problem and cant wait to get them 2 sensors changed to see how she feels ill message back tue night for the update.... hopefully good news