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

had to go hospital over my thumb lads because it didn't stop bleeding now ive got a thumb all bandaged up like a cartoon caracter who hit himself with a hammer. and im on antibiotics because the doc things the old import might be 'dirty' :)

update.. the electric fan appears to still be on wilst the car is running, but only if the car is warmed up, then turned off, then started up again(wilst still warm)

 

Its very wierd... any advice?

Could the chip not be telling the ECU to do that to ensure that the car gets a little more cooling going on because of the increased power etc? Just a thought if everthing else seems fine now.

Chip wouldn't change owt like that mate.

Fan is obviously thinking the car is going to overheat (beyond 100 degrees!) for some reason. From what's happend you may have an electrical problem somewhere either with the Aircon or in relation to engine temperature.

smithy

ok im hoping this is the last post in this thread now.

 

The car now drives perfect and starts from cold perfect, but if the car is already warm when started, the car seems to think it needs warming up again and she idles at 12-1300rpm for a few minutes and if you touch the throttle the revs drop before they rise.

But... after a few minutes/miles, about as much as would take to normally make the engine warm, all goes back to normal.

 

Wierd eh?

 

But never mind because the chip has removed some flatspots at high revs, COOL!

Problems started again,

 

Engine check light on, the car was parked up at work stone cold, started her up and the light came on along with the electric fan.

 

the ecu has not been moved,

 

what else would cause this problem?

 

Same as before, i cannot get an error code number because the red LED on the ECU is always on along with the fan and the car is in safety boost.

 

Urgent help needed

Sounds like the lead to the water temperature sender is intermittent. May need to be resoldered to a new spade connector or even checked/re-wired right back to the ECU. Water shouldn't have found it's way into the ECU, but it might be worth having a look. Maybe you could borrow a Conzult and see what the indicated temperature is when the problem shows up. I'd lend you mine, but someone else has already borrowed it!

no water around the ECU buddy, ive cleaned the temp sensor and it seems fine, but i checked this the last time too and it was fine then, thanks for the offer bud. much appreciated

which wires connect to/make the elec fan work?

Ok, ive just bumped into this thread on another forum and it seems to be true so mr andy p has agreed to help me out with another eprom,

 

I must say this bloke is very helpfull and i cannot thank him enough

update... andy has had a look at the ecu and tested it in his car, and his verdict is that its fine.

 

So any ideas???

 

Symptoms are :

engine check light always on

Radiator fan always on, (high speed) inc. Ignition

Safety Boost

Reading the post it sounds like the ecu temp sensor is knackered. Or the wiring for the ecu temp sensor has a break in it. One of the tests for the fan is to disconnect the sensor and the fan will come on. So if your fan is on with ecu check light you have sensor or wiring fault. Considering you have been removing the ecu, it's possible the break is at that end or you have done a common thing and overtighened the connector to the ecu so that the ends start to bow outwards. You don't have to do it up very tight, just enough to hold it in place

Maybe some one on here can tell you which wire going into the ecu is for the ecu temp sensor. Once you find that out ( sorry i don't know ) run a multi metre between the sensor and ecu end to see if you get a circuit or not. If you do then it is probably the sensor that is faulty.

i believe the ecu temp sensor is the only sensor that will tell the ecu to turn on the fan. If it was an air-con fault you wouldn't have safty boost or ecu check light.

 

Scott

ok mate sounds like a plan... found this to read too http://www.twinturbo.net/ttnettech/auxfan/auxfan.html

Hmmm, I seem to have missed 95% of this thread. Agree that a ConZult test is that is what is really needed to identify the problem. Anyone in the Macclesfield area who can help Pete out ?

glad u got it sorted soz to hear bout the thumb !!

 

had a viscous fan prob on a bm i use to own no use to u what so ever at the min i know!! but hey you never know for future ref

 

touch wood ur sorted though :-)

wish i could help more hope u get it sorted properly m8 but ur in good hands me thinks

300z, the problems not fixed... and its the electric fan... :rolleyes:

sound just noticed some one had mentioned viscous or somin? in a reply so thought would mention ill leave u with the experts m8 lol good luck :-):-)

I got my ECU back from andy P and and reinstalled it, cleaned off the sensors and made sure there wasn't any pull on the wires.

Everything was ok, not one problem, the idle was great and it drove like a dream. that was yesturday...

So today i got up checked everything was ok and installed some new dump valves and drove around all day fault free, everything was excellent, up and down the motorway, around and around the shops. Ive been everywhere

but Guess what... The Problems back again,

The engine check light is back on and the fan wont turn off when the ignition/engine is on.

 

Something is telling the fan not to turn off after it has reached operating temp to turn on.

 

What could this be?

Water temp sensor - double, double check the connector with the yellow plug on the front of the engine.

Nothing, its fine clean and clear, the connector is spot on.

 

Am i right in thinking the fan is speed sensitive as well as temp sesitive, ie it only turns on at certain speeds and temps?

 

If so, the speed part of the equation would be handled with the ECU, well... the fan is still on no matter what speed you do.

 

Is this right?

No, the fan is only temp sensitive.

 

What error code you you get after the ECU check light has come on ?

none, the LED is always on because the fan is always on

actually i think you might be wrong, this is taken from this link http://www.twinturbo.net/ttnettech/auxfan/auxfan.html

 

The TT Z32 has a two speed fan. The following specs are for the TT fan, and also come from the Nissan service manual with temps in Fahrenheit:

 

A/C off, coolant temp below 219 = fan off

A/C off, coolant temp above 221 = fan on

A/C on, vehicle speed

A/C on, vehicle speed

A/C on, vehicle speed > 25mph, coolant below 219 = fan off

A/C on, vehicle speed > 25mph, coolant above 221 = fan on

 

As you can see, the fan is ECU controlled (A/C, temp & speed sensor input feeds to ECU, output from ECU for fan operation). It is also obvious the fan should not run very often if the cooling system is operating efficiently.

Ok, I could be wrong, BUT if you have the ECU check light up then it should have an error code. If we know what that code is then we will know where to direct our attention.