Strange Fuelling problem

Had my car mapped by Ian a couple of weeks back and it has been great.

The only issue i had was it didnt always start very easily. It would turn over for a few seconds before firing up. Then when it did it would be very lumpy for 20 seconds or so (especially when cold). So i changed the spark plugs and this sorted the problem out. Fired up instantly and ran fine from cold

But has now started behaving a little strange. It seems to be overfuelling.

On the AFR gauge it goes off the scale (rich) when on boost, and when trying to start it again it has gone back to turning over for a while then goes lumpy for a while.

I went for a drive today and it seems to chuck out some black smoke and goes very lumpy especially when in 6th gear.

I removed the plugs again today to see what condition they were in and they are totally black. They look as though they have been in for 10,000 miles not a 100.

I sent Ian some datalogs from a 3rd gear run and it seems to be fine. AFR's are between 11.5 and 11.7.

So am a little confused on this, Ian has offered to have another look but just wanted to see if anyone had any other ideas.

Thanks

Bad connection on/or water temp sensor? (bad idle and over fueling)

faulty Fuel pressure VSV not allowing Vac and keeping fuel pressure at base? (over rich start up and rich off boost and bad idle)

O2 sensor (lumpy idle and fooked afr's in closed loop)

Boost leak? (rich on boost) though you say open loop is ok from datlogs, its more a problem

in close loop.

Will check the water temp sensor connection tomorrow.

Where would i find the Fuel pressure VSV, i have a Aeromotive FPR by the way set at 36psi.

It had a new 02 sensor about 6 months ago.

I am getting plenty of boost. 1.2bar by 3200rpms.

Scrap that your jspec, thought u were ukfor some reason - no vsv with yours. check the temp sensor.

Also could be the idle valve too

Cheers Marty will check that tomorrow, possible it has been pulled off by mistake i suppose.

Is there anything else you can think of?

Idle control Valve diaphram can leak causing weird problems.

(ive had a few drinks so will have a think and post up tomorrow evening lol)

Cheers mate

Also double check your fuel pressure if you haven't already.

I'm a bit stumped by this as Smarty sent me some datalogs and according to them it's behaving perfectly Exactly as it was when it was mapped. But now it's fouling plugs, hitting

Hopefully the next set of logs will show a problem

-Ian

Ian are these problems just in Closed loop, do the datalogs on wot etc etc look ok?

EDIT: just re-read

I'm a bit stumped by this as Smarty sent me some datalogs and according to them it's behaving perfectly Exactly as it was when it was mapped. But now it's fouling plugs, hitting

 

Hopefully the next set of logs will show a problem

 

-Ian

Ian i will go and do those datalogs in a bit and send them accross.

Thanks

no help from me im afraid...just want to know what ecu and datalogging you have?

cheers

no help from me im afraid...just want to know what ecu and datalogging you have?

cheers

If Ian mapped it, it will be an Emanage, probably an ultimate version.

Its the Emanage Blue Unit

Just off out to do these datalogs, back in a bit

That was fun

Ian you have mail

Am having some problems doing the datalogs this time, they are not working

So have been trying other things to see if there is a problem. The main problem is the starting of the car.

When its cold it turns over for 10 secs or so before firing up and when it does it chugs and kicks out smoke.

Thought i would check the 02 sensor and tested it as per the manual.

With a link between TE1 and E1 with the revs held at 2500rpms for 10 seconds, the multimeter (connected between E1 and VF1) it seems to fluctuate at least 7 or 8 times however its diificult to say as its a digital meter that seems slow to respond.

So went onto the next step which was with the TE1 and E1 link removed and the voltage measured between VF1 and E1 again with revs held at 2500rpms it reads 2.245v which according to the manual should be replaced.

Does this sound like a knackered sensor causing the starting problems and fouling the plugs?

Thanks

Just tried it using the method Ian C posted here and i am not quite sure what to make of it, seems to be all over the place

Warm Idle 02 readings

What do you think

That video is spot on, it's fluctuating between lean and rich as the ecu tries to balance the perfect mix. It would settle on a low or high value if something was wrong and closed loop ran out of adjustment range.

Steve emailed me a couple of datalogs and I noticed some fuelling anomalies, based around the amount of fuel the stock ECU itself sent out before any adjustment by the E-Manage. The E-Manage datalogs the duty cycle and duration that the ecu sends it, and also datalogs the final actual duration and duty cycle after the E-Manage has made it's changes. In these examples I'm using the durations that the *stock* ECU sent out to the E_Manage.

I got Steve to re-run a 3rd gear pull with his fuel pressure 4psi lower to try and get the fuelling in range of his O2 sensor. He did two runs, luckily, a couple of minutes apart in the same session (no engine restarts or ecu reboots). The interesting thing is that the first run overfuelled and the second one didn't... The reason for the overfuelling is that the *stock* ecu sent out much more duration to begin with!

Eg:

Run 1:

4000rpm, 1.15bar, 15.7ms

5000rpm, 1.25bar, 17.8ms

6000rpm, 1.19bar, 17.1ms

Run 2:

4000rpm, 1.16bar, 14.7ms

5000rpm, 1.23bar, 16.5ms

6000rpm, 1.18bar, 16.0ms

That's a *big* difference and meant run 1 went below 11.4:1 and run 2 stuck at 12.2:1 afrs...

The last test run of the day when we mapped it got these numbers under the same conditions:

4000rpm, 1.17bar, 14.2ms

5000rpm, 1.25bar, 16.1ms

6000rpm, 1.22bar, 15.6ms

So you can see that run #2 has the stock ECU for some reason putting out about 0.5ms more duration than when I mapped it. Run #1 has ludicrously more! 1.5 extra ms duration, no wonder the fuelling is all to cock and it's fouling the plugs up.

I've suggested a possible poor connection between ECU and Water temp sensor. The higher the resistance in that circuit, the colder the ECU will think the coolant is, so if there is a poor connection then the ECU will increase duration markedly. Steve recently replaced the water temp sensor itself, and that combined with the on-off variability of the problem leads me to believe it's not the sensor itself but probably the connector or the wiring. Investigations continue!

-Ian

Thanks for putting that up Ian, you explained it better than i could have

Have checked the sensor itself and that seems fine. It reads what the manual says at certain degrees.

Now one of the pins that connect onto the sensor is a bit dodgy. When it is pushed on it seems to open up the plug so much that it goes quite loose. So this may be causing a high resistance which would cause the ECU to think the coolant is cold, so would try to throw in more fuel.

Just trying to find a way of holding the pin there whilst i meter it from the ECU end to prove wether its this pin or not.

Does anybody know if Toyota sell the pins that are used to connect to any of the electrics?

I have a tool that should crimp it back onto the cable, i just need the pin.

Thanks Ian

I will let you know what i find

Have checked the ECU to Water Sensor cables. They are ok with no shorts. Also had the car running with my meter accross the water temp pins at the ECU (44 & 65) to see what was happening.

They read ok (as per manual).

Tried checking the Air Temp sensor (same method as above). That reads ok (as per manual).

Can anyone think of anything else that could cause the ECU to send out more injector duration?

The only thing left i can think of is the Stock ECU.

ps. Ian, sorry for ringing you all day for advice

What about the TPS, always causes weird problems. RE read circuit description here :- http://www.fototime.com/F6E3AA2A78D9BB3/orig.jpg

Maybe worth checking it..

http://www.fototime.com/64C2316565E91F7/orig.jpg

http://www.fototime.com/4DD907D434FC3A8/orig.jpg

http://www.fototime.com/F6E3AA2A78D9BB3/orig.jpg

http://www.fototime.com/7D9F09F39AB8CF5/orig.jpg

http://www.fototime.com/14670DCEA58FE3D/orig.jpg

http://www.fototime.com/0F95FCD79BFFF12/orig.jpg

My 1st guess was the Temp sensor, though you have now ruled that out it dosnt leave much..

Thanks Marty, i will have a look at that.

Have checked through the TPS, and that seems fine.

Have now tried a stock ECU, it was ok for the first couple of runs, now has gone to running rich again

 

Run 1:

4000rpm, 1.15bar, 15.7ms

5000rpm, 1.25bar, 17.8ms

6000rpm, 1.19bar, 17.1ms

 

Run 2:

4000rpm, 1.16bar, 14.7ms

5000rpm, 1.23bar, 16.5ms

6000rpm, 1.18bar, 16.0ms

 

Last run

4000rpm, 1.17bar, 14.2ms

5000rpm, 1.25bar, 16.1ms

6000rpm, 1.22bar, 15.6ms

 

Ian what were the TPS voltage/percentage values for the above. Im just thinking out loud here, but assuming a small boost leak (i.e. faulty Idle valve slightly open one minute, then ok the other) was in place, then you would require a Higher amount of throttle to acheive the same boost level per rpm as your original mapping. Which would naturally mean more injector duty from the ECU?

All i can say is the runs were done in 3rd gear from 2000rpms ish up to redline with foot hard to the floor.

Ian will give the technical answer