VR6 wont start

[toadt 10]

Hello, hope someone can help, Ive searched and I can find things which are similar, but not quite the same as my problem.

My car is a 93 vr6 with 150k. I use it every day and have done for years, and its normally ok, bit slow to start but fine when it warms up, other niggles but it works fine most of the time. Last week I took it 200 miles down country and back and it was excellent. Fair enough I was doing 50 a lot of the time, and trying to get good mpg, but I still managed to amaze myself with 39.8mpg both ways.

Anyway, now it wont start. Turns over fine but wont fire. Ive been checking the fuel pump and ecu relays, I know they can be an issue and ive had bother in the past with my last corrado with these. Seems this one might have problems aswell... Ive got the covers off them so I can see exactly what theyre doing. When I turn the ignition on the ecu relay closes and the fuel pump relay closes briefly then opens again, just a tap. As far as I know this correct. Then when you turn the key to start it the fuel pump relay is meant to close and assuming everything else goes well the car should start. Then the fuel pump relay stays closed till you turn the engine back off. Well my relay isn't closing when I turn the key to start. I know the relay works and that theres power to it because it taps when I turn the ignition on. I can close the relay with my finger and hear the fuel pump going. Ive tried trying to start it and pressing the relay myself but it still wont start. Ive also tried a different relay and the problem remains. Battery isn't an issue because I had it on the jump leads while I was trying to start it.

 

So.... if anyones had this or has any ideas please throw them my way :scratch:

[swiftkid 1]

Have you tried taking the fuel line off and cranking it to see if you are getting fuel? I'd be checking that first, also I wouldn't rule out having 2 knackered relays, I've had that problem before where a 'spare' part used to rule out something is also knackered. You could always take out the relay and jump the terminals to give it constant power though

[toadt 10]

Cheers swiftkid. I havnt tried the fuel line but I will have a look. Ill try bridging the relays aswell and see what happens. Im pretty sure theyre working Ok, ive got the covers off them so I can see them moving. Ill still check anyway cos its easy enough to do and I guess they cud be broke but still move. Ill be well happy if thats all it is

[toadt 10]

Ok, so cars working again today??? Relays doing what theyre supposed to and its starting no bother. All ive done is wiggle the wires that go into the ecu and make sure its plugged in right. coincidence? Will have a closer look to make sure wires are all ok and all the terminals on the plug are nice and clean. It did it on my drive this time but next time I mite not be so lucky so any other thoughts on the matter would be appreciated.

[Roger Chatfield 0]

Immobiliser possibly.... I had a similar non starting fault with 'Stormy' awhile back, I had to leave it in the garage and take wifey's car to work, had a look after work and the bloody thing started.... I vagcom'ed a few weeks later and it had an old immobiliser fault on it.

 

Also recently I've had a few 'slow starters' (started after about 5-10 secs of cranking), vagcom is slowing an intermittent cam sensor fault, maybe that could be your problem as well.

 

BTW, where in the country are you? if you are in Devon / Cornwall I'll be more than happy to do you a scan.

 

Rog.

[toadt 10]

Thanks Roger. The immobiliser is a toad cat1 so its not the standard one, would that still show on vagcom? It was already on the car when I bought it but ive got all the papers and stuff for it.

 

Cheers but im in Newcastle upon Tyne so it would be a bit of a mission. Ill get it on vagcom tho and see what it says. Whats involved in changing the crank sensor? Mine does take up to 5 secs of cranking. Had a vr6 before and this ones always been slower to start

[toadt 10]

cam not crank :bonk:

[Roger Chatfield 0]

I believe the later VR's had a factory immobiliser (I know mine has), it reads a code from the key, your toad is in addition to the factory fit, very rare for toads to go wrong.

 

My problem is not the 'CRANK' sensor, its the 'CAM' sensor, sometimes called the hall sensor, takes about 15 mins to change.

 

Personally I think you would benefit from a VAGCOM scan, there is a thread somewhere on here of people who are happy to do scans and their locality, have a look on there or put a post up asking if anyone near you can help.

 

Rog.

 

EDIT, just seen your last post, you must have wrote it while I was typing this.....lol

[toadt 10]

Haha yeah I noticed what id said just as I sent it. Thinking too hard about cranking.

 

It could do with a scan, ive never had one done on it. I needed to get one anyway cos the ABS light has recently come on. Ill have a look and see if I can find anyone round here who'll do one.

If its an easy job I might just replace the cam sensor anyway

[Roger Chatfield 0]

Easy job on a late (coil pack) car but its 70-90 quid new, not sure on a dizzy car, I think it's in the distributor.

 

Rog.

[Stonejag 10]

The stock (late cars) immobiliser is easy to diagnose - if the car starts and runs for 2s then cuts out, it's the immobiliser.

 

Reason being that it lets you start the car as normal but then stops it again if it can't read the code within 2s. Usually the reader coil (black plastic ring clipped on the steering lock housing over the ignition barrel) - you can get a new one out of a Mk4 Polo in the scrapyard for a couple of quid. The Polo parts has an extra tab on the connector so won't fit until you shave it off with a sharp knife. Hooks into the immobiliser box (black box with two connectors, about 4x2x1") which is usually located in the dash undertray under the rightmost dash vent. Pig to fit the cable (unless you remove the steering column) but at least the parts are cheap! :)

[Mawrick 0]

If this is a hot start problem, then maybe this can be the culprit - I tried pretty much everything else related to starting problems - mine had intermittent start problems, always had to crank the sh*** out of it when hot - never experienced again after this fix:

 

 

http://the-corrado.net/showthread.php?t=87352&page=3&p=1032480#post1032480

 

 

VW had a "fix" for the pump that was basically a non return valve inline hose - but it's sadly obsolete