Fitted my JWT dual POP on Saturday, bit of a tight squeeze but not too bad, however I did have a couple of issues......

 

1. After removing my AFM from the T piece, I discovered the mesh on the back was in bits and had most probably been shooting metal filaments at my turbo's for at least a couple of thousand miles......

 

2. Upon fitting the 555/dual pop chip my car now detts at about 8psi...........needless to say I'm somewhat unimpressed by this - any suggestions??:confused:

manifold pressure/boost pressure/throttle/other sensor not doing all it should? loose wire? loose connection?chip not fitted 100%? it has to be lack of fuel and i'd hazard a guess at it being something to do with the chip or something which has happened in the process of fitting it. dirty/broken airflow/mass meter due to the metal filaments coming back at it as you come off throttle? dont know if thats any help. just a few suggestions. good luck. si.:confused:

Must be running lean. Do you need to/have you remapped your S-AFC for the bigger intake capacity?? You will be running twice as much air as the MAS is now measuring I would imagine...presumably it's only measuring intake on one side now...(?)

 

Pardon my stating the obvious but - ECU reset? :)

Well the ECU was out of the car for about an hour, so that should be enough time for it to reset?

 

As for fuel......I chucked a load extra in with the SAFC, and it did'nt seem to make much difference. It was like there was a huge timing advance on the chip. Possibly.

 

The cars getting set up at DP on Wednesday with water injection...... hopefully we can get all the problems sorted out and be ready for the Pod on Sunday.....

did you have the chip mapped before the swap? could the resetting have lost it its new programme and sent it back to factory? if shooting a load of fuel in didnt help, is it fuel pressure and/possibly pump?

What time you hoping for if all goes well? :D

 

:bow:

Its a JWT chip designed speciffically for this application....

I'm running an FPR aswell as 555's and an aftermarket fuel pump, so fuel delivery should'nt be an issue....

Originally posted by pete shrimp

What time you hoping for if all goes well? :D

 

:bow:

 

Less than 13 fooking 4.....

 

Getting into the 12's would be nice......:rolleyes:

i gotta admit its got me. being electric/electronic, it throws loads of variables up. could be timing, but you would assume that the chip would take this into account as part of its design. if its detting at 8psi, is it detting at higher pressures? it really sounds like manifold pressure sensor. i take it the car starts and runs normally off boost? which would take out the tps and cps sensors. so if it runs fine off boost, we then know its something to do with the ecu not getting told its boosting or not doing the right thing about it. i would double check all the wires/plugs to anything to do with the pressurised side of things. 8psi is lower than safety boost, so shouldnt be a prob even in extreme cases unless the car doesnt know its boosting. hth. si.:confused:

FWIW it took my ECU a lot longer than an hour to reset last time I did it, hour and a half and it still hadn't done. Ended up disconneting the battery for the whole morning while I was at work to be sure...

 

Stating obvious again, presume you've checked all your new plumbing etc, no hoses buckled or split..? MAS is not back to front...?

 

I'd guess that the AFC is only measuring half as much air as is actually going in, no experience of AFC though so not sure how you'd tell it that it was measuring at 50% (!?) Is there an 'etc' menu like with AVC-R where you can program basic settings?

 

Good luck!

 

RobH

 

PS - where the heck do you get the money for this sort of fun?!?!

You tried asking on tt.net? A lot more people have twin POP's over there than on here.

Dave :dance:

I have to ask... Did you re-connect the AFM connector? :o

 

Check for ecu errors, and seeing you said you AFM could be in poor state check the voltages are correct... does your SAFC show this?

................the more you fiddle with it..............

 

 

 

 

 

 

 

 

 

 

 

 

 

;) ;)

Dave................Did you know you've got mini 'crop circles' on your lawn?

 

 

 

:rofl: :rofl:

 

 

 

 

 

...either that or one huuuuuuuuge car!

I would have a look at your detonation sensor cicuit!

 

Do you have access to conzult? You need to do a 'real time' conzult test to check all voltages etc.

 

What can happen is that if the detonation sensor is telling the ecu to run in safe mode then the ecu will try to switch off the boost control solenoids and limit boost / fuel / timing etc.

 

Your avc-r is bypassing the boost control solenoids and giving you the preset amount of boost although the ecu is not expecting this to happen!

 

You shouldn't have to add fuel with the JWT chip!! Normally you would make some fine adjustments with your AFC to lean it off slightly.

 

Steve E

Cheers - I was thinking det sensor:(

I had a new one fitted when I had my rebuild done in Jan this year, but I guess it could have been faulty:rolleyes:

Originally posted by AdamR

I had a new one fitted when I had my rebuild done in Jan this year, but I guess it could have been faulty:rolleyes:

 

Did you also replace the small wiring loom section?

 

Error code 34 is for the det sensor although it doesn't always show up on a diagnostic!

 

You need to run your car with consult / conzult wired up so you can see what is happening under all driving conditions.

 

I think this would answer alot of your problems.

 

Steve

Yeah I had the new loom replaced at the same time.

 

Do you think its worth doing a det sensor bypass, to see if it makes any difference?

Originally posted by AdamR

Do you think its worth doing a det sensor bypass, to see if it makes any difference?

 

No....I would just connect up conzult / consult and check everything in one swoop!

 

If a det sensor problem shows up then a bypass of this circuit would probably be the best way to fix it.

 

In your case (and mine) the det sensor does nothing to stop us blowing our engines :D

 

Steve E

LOL what a load of old *****x about cars :D;)

 

The hamsters are spinning the turbos too fast :D

 

No, seriously, Adam, what plugs are you running? Have you checked the fuel pump voltage at WOT? Should be 12v - its a dual voltage system which is controlled by the fuel pump controller (funnily enough :D). Sometimes the FPC goes faulty and doesn't give the extra voltage for the extra demand.

 

If you had forgotten the MAS connector then the engine would only rev to 3k. That rules that out. However, I would try swapping the MAS for a known good one just to rule that out.

 

Remove the S-AFC from the system completely. Get all the complicated sh!t outta there!

 

Det sensor circuit - NO WAY!!! this is ONLY to retard the ignition and lower the boost when detonation STARTS, NO WAY can it cause det ;)

Originally posted by andyduff

Det sensor circuit - NO WAY!!! this is ONLY to retard the ignition and lower the boost when detonation STARTS, NO WAY can it cause det ;)

 

Duffman.....your talking DUFF again!

 

How can the det sensor circuit lower boost when the boost control solenoids have been disconnected and boost is controlled by the avc-r?

 

Yes it retards the ignition and this combined with a different fuel curve and high boost preset by the avc-r causes massive heat build up on the exhaust!!!

 

And........Bingo you the perfect condtions for detonation.....too much heat and too high combustion pressure.

 

Apart from that.....your other points are also valid :D

 

Steve E

Erm, yeah - he's only running 8psi though so the car would do this with stock boost ;) No the boost solenoids aren't connected I was just highlighting everything that happens when SB is activated. In fact, if you REALLY want to know what EXACTLY happens when the engine detects det, just say so ;) Also, at 8psi you certainly won't get EGTs high enough to cause det - you'll just burn the turbos up a bit quicker :)

Originally posted by andyduff

Erm, yeah - he's only running 8psi though so the car would do this with stock boost ;)

 

8psi on Hybrid T28's....that's still a reasonable volume of air being forced in, especially on Adams setup! We're not talking kittens breath stock turbo's here!

 

Originally posted by andyduff

No the boost solenoids aren't connected I was just highlighting everything that happens when SB is activated. In fact, if you REALLY want to know what EXACTLY happens when the engine detects det, just say so ;)

 

We know what the manual says about the det sensor circuit! The issue here isn't what happens when the engine detects det, but what happens when the det sensor fails intermittently!! I KNOW because I've have it and watched what happens on the open road using Nissans consult!! A faulty det sensor is a big PIA outside of limiting boost and retarding the ignition timing.

 

Originally posted by andyduff

Also, at 8psi you certainly won't get EGTs high enough to cause det - you'll just burn the turbos up a bit quicker :)

 

You could also make a statement that you certainly won't get detonation at 8psi.... but hey, Adam is getting it on his Z. You don't know his EGT at 8psi because you don't what what the engine is doing!!

 

I've seen detonation on a car running 800deg EGT and no detonation on a car running 1050deg EGT

 

Steve E:slap:

PMSL:D Hey Duffer and Steve you fancy a few rounds in fight club?:D;)

I can't wait for the next round !

 

:slap:

Originally posted by Jez

I can't wait for the next round !

 

:slap:

 

Hi Jez.....how's the new turbo running?

 

The det sensor & code 34 has alot to answer for!! I blame it for writing off my last Z....

 

:eek:

 

Call you later ;)

 

Steve