Rogue_Ant

What are the ohms of the resistors that you used? Have you tried running the injectors without the resistors?

-Rogue

95ONE

1. When did you let off the gas?

A. 5Krpm

2. Looking at the graph you posted you hit 3psi at 3k rpm and everything kinda goes flat. Obviously when you let off the throttle it should go really lean, so it makes it unclear when you let of the gas on the dyno

A. Actually it hit 3 psi at 2700. and it was suppose to stay at 3 psi. This is all I wanted to start at. It's not the psi I was worrried about. when the Dyno ends is when "I " let off the gas. It was full throttle all the way through, I just watched it hit 15 A/F at 4K rpm gave it to 5Krpm to correct and it didn't. So I let off.

Lots of details to keep track of though.

95ONE

It's a 3psi spring in there. I have an Electronic boost controller to turn up the boost. On that spring. the controller can force it to go up to 17psi. I had another Vband 44mm Tial waiting to swap out when I need to go further. it takes 2 minutes to swap.
But. The pressure wasn't the issue. 3 psi is what I was starting off with. With plans to up the pressure with each run as long as A/F were ok. Never got past the starting point becuase it was running stupid. Extremely dis- appointing.

The confusing part of the day was that the car was running completely different (correct) right before I parked it on the trailer to go to the dyno.

95ONE

1 ohm.

I'm thinking that's a good guess also. I just hope I haven't hurt my injector driver on this set of computers. (3rd)

I'm taking them out. I have the harness completely pulled apart. everything look pretty good and is testing out perfect as before. SO this is all I have left to change

I am however completely re-wiring every wire to the Dme concerning MAF, TPS, Injectors, and Coolant temp. Completely new wires. I don't want to mess with this harness again. So it will be done tomorrow.

zoltan944

what did Vitesse say the chip is mapped to do at 3psi?

honestly I would set your boost to 8psi and hit it and watch your WB. Not going to have a problem with a 14 range ration at that psi until over 5k, basically let off at that point if you don't see what you want. If your worried about being rich in the first place adjust your maf translator to ensure more safety.
Before I spent more money and time I would see what your car does beyond 3 psi

zoltan944

that does suck. I can personally attest to some back luck like this. I had a perfectly running and runed car. Trailered it down to san diego took it off the trailer and it never ran right when it got off the trailer

This problem will eventually get worked out!

blown 944

Are these the same injectors you were previously using with the other DME's (pre mess)? IIRC this is a no.

If not, can you go back to the old setup temporarily (smaller injectors, old chip,AFM) and and backtrack to make sure it is not the DME and harness or other ??

I have had stupid problems my self. At one point I was chasing down a high RPM high boost cutout and it ended up being plug gap.

Then I had a problem with a HOBBS switch going bad at a most inopertuned time.

marky522

Sorry, I was trying to help you diagnose the problem, you should have told me you wanted the easy way...

If you want to check the voltage drop of your injector harness ( i blieve its actually 2 circuits batch fired correct?) You will need to run 1 wire from an injector into the cabin, and the correspoding pin from the DME, you are basically comparing voltage on each end of the wire, if there is resistance in the wire, it will consume some of the voltage and you will get a reading, .5v is spec but it should be a little less. Set your DMM to MIN/MAX and take it for a ride and make it act up. Then switch to the other injector wire. I believe you would have to do this for both the power and ground side. Or just keep throwing money at it....

Mark

95ONE

LOL! you take me too seriously. I appreciate the further input on how.

Sounds aesome. Not too difficult at all then eh?
This is why I did the fabrication and mechanic work and my tuner did ALL the electrical. It truly handicapped me by being able to ignore all this stuff. now I'm paying the price, but learning alot, real fast.

This is a fantastic idea. I will do this after I get my harness all rebuilt today or tomorrow.

95ONE

Same injectors that worked flawslessly before. I did go back to the old set up, with the old intake and manifold. With someone elses known workinf AFM with a borrwed ECU and stock chips with their stock Injectors. I replaced all that stuff.

Did the same $hit. continually gets leaner starting at around 4K and above.

Had to be something in the wiring. Resistors or something. - or hose to FPR. something. Cant try out these changes until tomorrow. Fingers Crossed so tight, they're numb.

HansB

We had two cars with similar problems lately. Turned out to be
1. the reference sender, throwing the timing off
2. a bad spark plug

schnellfahrer

I had a grounding issue; car would run crazy rich whenever at wot.
I changed the light switch in the driver´s side door before the weekend and the problem appears to be gone.
I hope it stays that way.
Chasing grunding issues is a b"#$%!

95ONE

ok.
ref sensor.
this caused car to go lean?

95ONE

oh jesus. a door light switch!? man if my problem is that far un-related, I'm screwed.

eniac

Years ago I spent nearly a full week trying to track down a similar problem. I checked all my grounds, wiring harness, injectors, fuel pressure, etc, etc. It was a weird thing as I kept concentrating on the injectors, drivers, and harness because if I disconnected one injector plug, the car ran as I would expect it would on 3 cylinders but would not with it plugged in on 4. It really seemed like one injector was not firing everytime it should have. It turns out the problem was a hairline crack in one of the spark plugs. I replaced all 4 plugs and the problem was immediately gone for good.

I think the cracked plug was making an arc and somehow interfering with the injectors firing as they should.