Bugger!

 

Just got my ECU back from mr andy p with a nice new chip, installed it no probs and took her for a drive.

All was fine about half hour into my drive i pulled up at a car wash and let the lads set about there work and whilst they were spraying her an engine check light appeared.

I start to reverse out and my car stalls and will not turn back on, engines turning but would not fire, after a few minutes trying it started with the engine check light still on.

I pull out of the wash bay and park up so they can do the inside.

 

10 - 15 mins later the car is dry and clean so i get back in and fire her up no problem, (engine check light still on) and start to drive home so i can fiqure out the problem.

The car is idling high about 1300RPM

Everytime i touch the throttle lightly the revs drop to a near stall, if i touch the throttle heavy it revs fine.

 

I pull over a few yards from the car wash and notice that if i put just the ignition on i can hear the sound of the fan but the fan doesn't spin (didn't used to do that) but when i fire her up it spins.

I also notice that everything sounds louder, exhaust, revs, everything...

I looked around the engine and nothing seemed out of place, no oil, water, no loose connections nothing.

 

I start to drive home and it starts no problem (engine light still on) and notice that it feels like its holding back, still droping the revs whenever i press lightly on the throttle and whenever i let off the pedal.

I try to give her a boot to see if she'd boost and she wont go past 7psi (ish) and wont go above about 4-5k RPM.

When i tryed to get higher it developed a missfire so i backed off.

 

Got home and left it for 10mins, went back to her and now she wont even start, just turns and splutters...

 

Its a early 92 JSPEC Auto TT, with what i believe to be a UK ecu

 

Edit - Skip to Post 45

Edited September 13, 200817 yr by petes21st

It could be water got into the air intake//MAF, as for your fan its a viscous fan and only runs when the engine is running, unless its been converted to an electric fan.

update...

 

just done an ecu error code chack and it came up code 55,

by magic now the car is fine...

 

mabe when i put the ecu in the car after getting it back the little pot wasn't all the way to the left. wierd

 

ill keep you informed if i get this prob again

update...

 

I tried to put the ecu in and its doing the same as before, the fan noise starts and the led on the ecu stays on so i cannot get a code

Can you confirm by fan you mean the electric one in front of Rad ?

and just 1 warning light or is there more ?

smithy

no, the viscous fan, it makes the sound of the viscous fan but the fan isnt spinning.

and the light is on permanantly, doesnt flash even when i retry doing a code check, it just stays on

Sounds like the electric (back up) fan to the front of the rad. I've had that if i dont fit the ecu back in a set way (thats odd i know). maybe you need to un bolt unit and large connector and bolt back, worked for me. Maybe on yours it got abit wet from the car wash (dont know).

sorry, i tell a lie, it is the rad fan, and it is spinning.

 

please can somebody point me in the direction of the connector mentioned in this thread

http://www.300zx.co.uk/forums/showthread.php?t=6338&highlight=fan+staying

 

i cant find it

Okay, it all seems like the chip has died to me.

Can you go out to the car, turn the ignition on and then go and put your ear near the front number plate, is that where you can hear the wurring noise for the fan ? if so, start the car and you should see the viscous fan running, now put your ear to the front of car again and you should also hear an electric wurring sound as before ?.

Finally with engine running, are there any dash board warning lights on ?

Oh and have you got an aftermarket vent in your bonnet ?

smithy

will try

 

ps. it was your answer in that thread

no vent smithy, and a engine check light

Okay now we know the electric sub fan is coming on and you have an engine check light, you have an ECU problem IMO.

Either it needs re fitting properly or am afraid the chip has fried, the only way to know the latter is to whack another ECU in, fan should stop and light goes out.

The reason you can't boot is cos it's in safety mode and also dumping excess fuel in the system.

IF you didn't have a warning light, it would then point to a faulty temp connector on your inlet water pipe.

hth

smithy

ok thanks, i just unpluged the loom onto the ecu and refittited, the car started fine, 30secs later the fan kicks in and it stalls,

 

i restarted and the fan is on and the light is on, i loosened the loom and restarted and it was fine, 30secs later, it stalled and the lights come back on

Strange it takes 30 seconds to go wrong, but certainly it's an ECU prob IMO mate. As i said if someone local with a Zed would pop by and just whack their ECU for 2 mins would 100% prove this.

smithy

tried to plag/unplg the ecu slowly and i can hear as the pins connect, the fan starts everytime, so i took off the headlight panal and tried to get to the connector wilst it was on, and i put my ****ing hand into the fan

 

now ive got a broken thumb and bleeding all over

also tried cleaning the temp sensor, no luck

also tried cleaning the temp sensor, no luck

Sorry mate it ain't that cos you got a warning light on.

just going back one post, did you say as you connected the ECU the fan came on ?? was the ignition turned off whilst you were doing this ?

smithy

no always on

So no igintion on, no key in the barrel etc the fan is always on ?

ta

smithy

yeah, im playing about with it at the min, it seems like the problem is the wires that plug in, in certain positions the fan doesnt come on in others it does

im trying to get it all back pluged in and bolted down and fidget with the wires wilst turning on/off the ingition until i dont hear the fan come on, its hard with a broken thumb and theres no telling i wont go over a bump and it wont start again

Ah not good mate. Can't think why it's getting power with no key turned, it has an "overrun" built into i think so it carries on running cooling the rad down after overheating, but am not a 100% on that. If so, it could explain why it's getting power with no key.

Have a read of this link mate, too much for me, lol

http://www.twinturbo.net/nissan/300zx/tech/auxfan/auxfan.html

smithy

hang on, got the ecu back in bolted up and all seems well, but ive noticed small carbon deposits coming out of the exhaust, anything to worry about?

ok, been for a drive and all is well, and ive answer my own question... the carbon deposits are caused by unburnt fuel in the exhaust from when it wasnt running right and when it was spluttering whilst trying to start. (fuel wets the carbon in the exhaust and is blown out when running)

 

thats the conclusion ive come to anyway, especially considering the amout of fuel thats gone from my tank (bugger!)

 

So to sum up for 'search readers' the whole problem was caused by the wiring loom to the ecu not being situated correctly.

Maybe one of the wires is getting interference from another, im not to sure.

Also please note : do not put you thumb in the radiator fan - it really hurts!

Glad yer got it sorted mate and yep as said earlier excess fuel was being pumped incase of overheating which is what cause the fan to come on at times.

well done and poor ole finger dohhhhh

smithy

do not put you thumb in the radiator fan - it really hurts!

 

Top tip:smash: