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Hot start up problems (yes another topic! sorry!)

Outrun944

New member
Hi chaps

Firstly yes I've searched on the forums and found tons of topics on the subject, very useful - but am opening this as I'm under pressure to get the car back on the road for the weekend for various reasons, and I have a DME relay replacement coming tomorrow morning so if that's not the cause/fix then I want to eliminate other possibilities. Sorry. [&o]

I've not had chance to inspect the DME relay itself for worn/broken solders, the cars at my mates garage and we only just thought of this after researching here 10mins before he had to close.
But he's already -

Replaced DME coolant sensor / fuel sender switch
2bar pressure on fuel rail - sending fuel seems OK
Inspected air flow meter - this was already taken apart and contacts cleaned a few months - along with replacing the air box (rubber tube) as that had cracks, distributer cap and rotor arm (this did actually help improve cold starts)

Someone mentioned in a topic about the oxygen sensor ... is that the same as the air flow meter or something else entirely?

I think next we would look at bad earths and wiring loom from what I gather.


THE OTHER PART OF THIS! ie could this be all linked....

Anyway all this occured after I got a battery warning light come on driving home ... it stayed on and volts were getting very slowly lower, turned off everything I could but it was pitch black and chucking it down (arggh wipers getting slower!!) and managed to limp home and then to my garage in the morning with it sat around 10.5V on the dial. Turns out the alternator had gone (obviously) and I've had it repaired/reconditioned - he rang me to tell me burnt out it was inside! really bad!! Not seen it myself though.

We put the alternator back on, and this is when the hot start issue occuring. Again, its been at my mechanic and garage and not driven it myself to see, but its apparently really bad and not in a drivable state.

How could all this be linked? Thoughts?

Appreciate any input!

Cheers,

Al
 
Don't think the DME relay has anything to do with it, it either switches or it doesn't.

Hot or cold makes no difference.

I'm going thru the same issues, I notice that when hot and not starting the rev counter is immobile, then it comes up, and whehey it starts.....

Something is suppressing the sparks methinks, or could it be the wrong plugs???

 
Hi Al

You don't have an oxygen sensor, its only on late cars.

Does it turn over ok? And start from cold?

Could be FPR as should run at 2.5 Bar, pull off the vac pipe and smell for petrol.

Could be wires / plugs / sockets to AFM or temp sensor (my 1st choice I think)

Hope you get it sorted mate.
 
Hi Al

You haven't given details of what happens but I'd suggest taking a look at the idle control valve.

Pete
 
Al could you describe exactly what is happening now, when you try to start the car ?
I'm a bit confused about the sequence of events .

Does it actually start and run now?
Is the problem that the engine will start and then not restart when hot ?

 
ORIGINAL: A9XXC
Does it turn over ok? And start from cold?

Apparently so yes. Because I've only had fleeting convos with my mechanic (and he's a man of few words at the best of times!) due to time pressures of his other work load and trying to get this sorted after a couple of days - sorry I can't be more specific.

Could be FPR as should run at 2.5 Bar, pull off the vac pipe and smell for petrol.

Fuel Pressure Regulator yea? I'll forward that on to him.

Could be wires / plugs / sockets to AFM or temp sensor (my 1st choice I think)
Hope you get it sorted mate.

I think he's already checked this, having messed about with the AFM and temp sensor already - but I'll remind him.

Thanks Mike!


Any idea how the alternator blowing links to all this though? Or just one of those coincidences?
 
ORIGINAL: peanut
Al could you describe exactly what is happening now, when you try to start the car ?
I'm a bit confused about the sequence of events .
Does it actually start and run now?
Is the problem that the engine will start and then not restart when hot ?

Hi Peanut, thanks for the reply and I'm very sorry I'm not more forthcoming with details and specifics at present - annoying I know for people to reply to.

Basically the car has been at my mates garage for most the week, and he's quite a few miles out - so it's a long bus journey out - so I'm having to go on a few 5 minutes convos on the phone with a man of a few words at the best of times (but a very good mechanic!) and I've not physically been present either and tested myself. So it's quite possible some of what I've relayed here isn't correct. I will have more definites tomorrow and I'm just desperate to get it working otherwise hire car time again *sigh* but want to be prepared tomorrow with suggestions to look at and other possibilities as I get the feeling he's struggling now if the DME relay doesn't do the trick.

> Does it actually start and run now?

Yes, but it's very rough and not idling well. Road tests are not good, with it kangarooing at times but...

> Is the problem that the engine will start and then not restart when hot ?

The engine will start cold or hot, but it seems when hot its very rough, not idling correctly, about to cut out and will in fact cut out on occasion
 
I'm just a little confused about ...

Alternator dies
Alternator repaired and put back on
Car now has startup issues

What could be the link? Or just pure coincidence?
 

ORIGINAL: Outrun944

ORIGINAL: peanut
Al could you describe exactly what is happening now, when you try to start the car ?
I'm a bit confused about the sequence of events .
Does it actually start and run now?
Is the problem that the engine will start and then not restart when hot ?

Hi Peanut, thanks for the reply and I'm very sorry I'm not more forthcoming with details and specifics at present - annoying I know for people to reply to.

Basically the car has been at my mates garage for most the week, and he's quite a few miles out - so it's a long bus journey out - so I'm having to go on a few 5 minutes convos on the phone with a man of a few words at the best of times (but a very good mechanic!) and I've not physically been present either and tested myself. So it's quite possible some of what I've relayed here isn't correct. I will have more definites tomorrow and I'm just desperate to get it working otherwise hire car time again *sigh* but want to be prepared tomorrow with suggestions to look at and other possibilities as I get the feeling he's struggling now if the DME relay doesn't do the trick.

> Does it actually start and run now?

Yes, but it's very rough and not idling well. Road tests are not good, with it kangarooing at times but...

> Is the problem that the engine will start and then not restart when hot ?

The engine will start cold or hot, but it seems when hot its very rough, not idling correctly, about to cut out and will in fact cut out on occasion



Ill repeat, check the idle control valve...:)

Pete
 

ORIGINAL: Outrun944

Thanks Pete! Will do and will pass it on to him, but I'm assuming he may have already looked at this


well I hope you get it fixed quickly.... I'd get the car running and when it starts running rough try tapping the valve to see if it clears, also you should be able to hear the valve click when turning the ignition on, another possibility could be the throttle position switch, certainly worth looking at considering the obvious things that he's already checked.

good luck

Pete
 
sticking throttle valve plate ?, may need cleaning , mine was very dirty where the oil breather pipe fed into the throttle body .

Nick [:D]
 
sorry i typed a really lengthly reply (20 minutes ) and this cra**y site timed out again and erased the whole post so I lost the whole thing. it then locked me out of the damn thread and I had to relog in again, grrrrr.[:mad:]

This is not the first time that this has happened recently and it really is a pitta. last time It prevented me logging in again and I had to re-register ?

This site has some bugs for sure.[:(]

i've totally lost the will to re-type 6x paragraphs I'm afraid so I'm off to bed . [:mad:]
 
Nevermind Peanut, thanks anyway. Forum could probably do with an upgrade and have a garage section like other car forums I used to frequent.
 
I'll have another go tomorrow [:D] when i've recovered some sense of humour lol.
Basically I was suggesting checking the vacuum system for leaks and then clean the earths before doing anything else as they often seem to be the most common culprets .
 
Ok thanks! Look forward to your post tomorrow, I'll be off to the garage before midday armed with all this info!
I'm hoping it's just a knackered DME relay, all the other topics I've found the common answer/response is that it seems.
 
if you replace the DME relay with the 3x wire bypass and there is no change you'll know for sure that the problem is not the DME relay, otherwise you never know for sure if the relay is playing up, even if its a new one fitted.

On the base of the DME relay socket the terminals are numbered . You need to connect terminals 30, 87 and 87b together . This will power the ECU ,injectors, ignition amplifier and fuel pump which you should hear pumping continuously.Be careful because terminal 30 is always live even with the ignition off .


 
It's not the DME relay :(

FPR is OK ... its at 2.1bar on the fuel rail and will shoot up if its taken off and clamped down, so it's doing the job it should do apparently.
They've looked at idle control valve too as well as the vacuum system

They're a bit stumped now :(

And asking me now for workshop manuals on component testing on engine management side, so am scrambliing to find this before they have to close :(
 
OK I've got the workshop manuals now.

I'll update with a full detailed overview of exactly the issue and what has been done and tested so far in a bit.

*sigh* Looks like hire car time then.
 

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