Ok,

 

problem has changed over the past 3 months....

 

started with running a bit rough on start up, then driving down the motor-way, all of a sudden car would run really rough in 5th under load, then in any gear, had to pull off motorway, turn off car and restart OK. (but it wouldn't happen all the time)

 

So I got another set of coil packs, fixed the rough at start but still had the same problem on motorway.

 

bought a new PTU, fitted that.... no difference... Cleaned the contacts for the CAS and that seemed to make it a bit better......

 

replaced the air filter and cleaned the contacts, cleaned the contacts for the TPS and any other I could get my hands on still the same...

 

So now seems to run fine, starts and warms up OK, on motorway under load seems to boost fine but again problems in 5th under any load, car hesitates.

 

i've put in on the free version of conzult, no error codes but strange readings from IACV (way too high) & O2 readings (up and down at idle, 0.1 to 0.8) ...

 

I did a 40 mile trip and them took these readings on the driveway... any help & advice much appreciated.

 

I don't know about the rest, but the O2 sensors are supposed to do that, alternate from high to low, or rich to lean...

have you done a manual conversion?

Ah... not me personally... but the car was converted....

 

new engine, manual conversion... with new ECU... I checked the ECU part number and it is a manual one.. the car is originally a 1991 JDM auto tt, the engine was from a 1992 donor.. not sure where the ecu came from or what year it is.

saying that, it was running fine before... this kind of just started...

The readings you have there need to be done again when the engine is not running so HOT!!!!! 93c jeez!!!! you going melt it if that continues to rise.

 

Some of the readings will be effected by the high temp, the aac is way to high at 62% should be 15% at idle, this could be raised though due to the high temp, The injection pulse is quite low for stadard injectors at 1.8m sec, should be more like 2.1 msec are your running different injectors?

 

The closed throttle is missing and by the way the 02 sensors are supposed to read up and down as they alternate between lean and rich to give a mean average.

 

***IMPORTANT***

One thing I cannot stress enough is to look into the very high coolant temps, this is the number one killer of zed engines.

 

Once that is sorted see what the readings are then.

 

Jeff TT

I was just thinking whether the timing should be at 25 degrees instead of 15, depends on the neutral switch, another one for JeffTT!!! And 95 degrees temp on one pic, crikey, that is hot!

Ah yes..... I did give it a bit of a run..... and then just sat on the driveway after wards (quite a steep uphill slope, if that makes any difference)..

 

thanks both....

 

I've look at it before after a warm up... constant 80 C and AAC is still too high and always is.

i'm running 555 injectors.. (silly om me not to mention)

what are the causes of a high AAC reading?

I wonder if JefTT would so kind (he probably already has) as to post a picture of the ideal readings? I have conzult and will be doing a good check up soon...

Ah, yes he already has.... I've checked previous posts and printed them off.... however I couldn't find the solution to high AAC.... if it's the unit then i can replace it but if it's something else obviously i would need to address that.

i was hoping it would be a simple common thing but it might need me to take it to him... unfortunately it's a bit of a drive....

 

on the high temp side I'll have to check that the electric fan is actually working...

since most of my driving is motor way and very early or evening the temp stays low..

on the high temp side I'll have to check that the electric fan is actually working

 

Run for the hills she is gonna blow!!!!!!!!!!!!!!!!!!!!

 

here is what you need to do to get the engine temp down and SAFE

 

remove the electric fan and put it in one of these

 

Any one dont worry about getting the correct colour because either way you will be saving the planet from a melted zed!

 

Then reinstall the viscous fan that Nissan spent £££££££££ developing to keep their Z32 engine at the correct temperature.

 

Ok all joking apart I am yet to be conviced that any electric fan currently been marketed can keep the z engine safe, with electric fans they mostly run too hot and at some times way, way to hot.

 

If you measure the blade surface area multiply this by the amount of blades, then add the speed of the blades and the pitch angle what you end up with is around 3,000 which by sheer chance is around the cost in pounds of a rebuild after the engine has gone into melt down!!

 

Over the past 2 or 3 years the amount of overheated zeds we have dealt with has increased, the number of electric fan kits been sold has also increased...... no mystery there then.

 

Sorry Medaliion Man if that sounded sarcastic it was simply to get over my point about the dangerous temp readings of your engine please concider putting your viscous fan back on, if you dont have it let me know I will send you one.

 

Ok the high aav reading can be caused by a lack of hard idle switch which could be caused by an incorrect setting,poor connection at the tps or even a wiring issue, its also possible the free diagnostic software not having all the functions on it, the screen you have posted does shows it greyed out when it should be bold?

 

A very low base idle setting will cause the aav to go high reading too, try disconneting the yellow plug on the top of the aav unit to see if the revs drop to next to nothing, if so the base idle screw is on the side, anti-clock wise for higher revs clock-wise for lower revs, any changes should be made with the yellow plug disconected or if the software allows in the tickover screen.

 

Jeff

Good one, thanks Jeff....

 

I bought the car with the electric fan on it, so unfortunately don't have one to put on (please pm me with details).

I'll do as you advise and check the idle without the aav..

 

could this be causing the hesitation?

 

your advise is most appreciated...

 

Gerry.

OK,

 

first pic is of car after warm up and little drive....

then unplugged AAC and took second pic..... idle dropped 100 (or so), turned screw up and then down …. Didn’t seem to make any difference, plugged it back in and revs go up again !!! how far should it be turned before noticeable change in idle?

 

cheers....

 

looking at the instructions for this I think I may have done it wrong... it says to turn the car off, unplug the aac then start it up and adjust the screw...

 

I did it all with the engine running.... might have a go at doing it the other way.