t4 problems over fueling to the max.??

[Golf Loon]

This van is cursed guys.

We tried a different ecu, luckily its an early uncoded key car so that was easy.

Same symptoms.

Change the two water temp sensors on the water outlet, cleared the codes with the 1551 and cleaned the dissy cap. Checked the timing, all good there.

Then the car started. Sounded sweet, consistantly started a few times and ran.

1551 was getting no codes at this point.

I then left and Brenton changed the second hand sensors I brought for his original new ones and drained and replaced the oil and the water.

Van now does not start!

I suspect the sensors, even though they are new, but will probably have to go back out to the boondocks to find out.

What do you blokes reckon?

[gregozedobe]

Logic says it is the sensors or someting to do with them eg wiring (can't see oil and water change causing faults). Of course logic sometimes doesn't work The other thing that comes to mind is some kind of connection/wiring problem (intermittent fault that sometimes passes current or shorts out), maybe a poor earth ? Worth chasing down and fixing properly, otherwise the van is going to be unreliable even if it does magically seem to cure itself (these sort of faults always seem to re-occur at just the most inconvenient time). Hope you get somewhere soon.

[h100vw]

I'd have a look at the sensors for sure. Very simple things, you can check them with a multimeter and a heat gun. Once you establish which pairs of contacts do what.

I think we are talking about 4 pin senders in the top hose, 2 are for the ECU and 2 for the temp gauge.

Compare 2 senders if you can. They should have a similar resistance at ambient temp which decreases if you warm the sender up. You should monitor the resistance of the suspect one as the temp changes, as it could be going open circuit at a certain temp. The ECU would see a high resistance, which it assumes is a mega cold engine and stick in loads of petrol for cold running.

Gavin

[Golf Loon]

Just got home and someone has nicked the two sensors out of my van
I reckon we should have an answer soon.

I suggested wiring, as some of it is a bit ratty.

Give us an update Brenton.

[Jmac]

One thing i would try and this cured a PB engine Gti with similar issues. Go straight to the ECU and find the earth. cut from main loom and then run from ECU to a solid well known Ground point and try it. Dont loom it up this stage in case of no fix but just run a length to ground. High resistance over time can affect the ECU. They are very tempremental. And age does get the better of them. Sounds like wiring as you say the lom is ratty. I would try the earth thing man. The Golf i did has been sound ever since, this too is digifant, Trans is digifant (early) or SIMOS.
GIve us an update.
CHeers

[DVR68U]

well i have already earthed the bolt that the ecu earth is connected to , so the ecu earth runs to the body above the ecu and i ran a direct earth from the battery to that point so the 2 are touching and also earthed to the body.
the wiring isnt that ratty it has had some body silicon the backs of all the plugs to stop the dirt and water getting in them.
today at 3 i went out and thought i would just give it a try with out changing anything. and sure enuf the bloody thing started. not running cleanly tho. turned it off then started again. then i let it cool down abit and changed the sensor back for the ones i got of matt. which are the not the ones i had in the car when this all started. i then tried to start it and it started and seemed to run on 3cly, i pulled leads while running to see which one wasnt firing and they all affect the idle. i let it idle for a bit more, walked about 5ms away and it died , and wont start again . so it started after it wouldnt yesterday with out changing anything.

[h100vw]

What Jimmy is saying is open up the loom at the ECU and hook another earth wire to it. Strip the wire and solder a length to it and earth that, back to the battery is best.

Could be the wire is high resistance through the crimp at the earth point which is affecting the voltage the ECU sees. Low voltage at the ECU causes it to richen the mixture.

On G60s it is a particular problem because of the forced induction, they billow black smoke.



Gavin

[DVR68U]

so the connector to the ecu, find the earth in the connector link it straight to the neg terminal, thats what you guys mean . i might find the pin and check the resistance of the circut before i cut it all up. if i get a chance 2morro ill have a go at it. trying to get the damn thing ready so i can take it down to summernats lol. tic tok
cheers brenton

[DVR68U]

also once the ecu has been fried will the car run at all ? the injector driver screwed up etc ?
cheers brenton

[Jmac]

Yeah just to clarify find the earth wire at the ecu plug, instead of splicing into it cut the thing all together and join it to a new wire and run it directly to earth. So you should have the ecu mutli plug with all the wiring as normal apart from the earth, this will be seperate. Open the loom up its the thick brown wire and cut it. I know im repeating but i might not have been clear. Now that the wire is cut. Connect a new wire to the ecu side of the cut and run it to earth. Fried ecus can be weird just depends on the way that its been fried. They can run but most often they run awful and fill the cylinders .
Hope thats a bit clearer ( i do waffle a little bit) And just to add to H100W comment he is spot on this fault used to happen to the Corrado G60 and was a VW technical Bulletin and referred to re routing the earth and cutting the crimp off.
Cheers