moalaska

I can accelerate pretty good but it just decides to lean out at least that's what it looks like. I can cruise past 3000 but if give it too much throttle at that point it stumbles and pops. I was thinking tps too. I replaced the closed throttle microswitch in the tps. It tests good on the contacts at the tps. I know i did the tps test procedure at dme harness a few months back that's how i found my problem with microswitch originally.

when i originally set up my car i was having fueling issues so i decided to just install an adjustable fpr withguage so i could be confident of my fuel pressure, I had thought the 3 bar that I had was no good. However most adjustable fprs dont hold fuel pressure after shut down. I installed the check valve to reduce fuel leakdown as I was getting vapor lock after letting car sit for a bit.

I dont have mo monitor for my vitesse system if im going to upgrade i might as well go stand alone

i haven't checked klr solder joints. I have resoldered the entire dme. I could go through klr i suppose. Dont have acces to spare. Was considering buying that ftech9 dme to eliminate 30 year old component as problem but then saw the vems pnp and im very much thinking about that right now.

Tom M'Guinn

Yes, there is a built-in resistor. The amount seems to vary by brand, but a recent Bosch had about 1k ohms.

fast951

Based on your description of the issue (please correct me if I'm wrong), it appears that the issue is related to load/boost more than RPM.
If you can cruise past 3000 RPM with light load, then it's not RPM specific. When you open up the throttle, around 3000 RPM boost starts to build. Could you confirm this?

You mention there is "popping" and it goes lean. Is the popping coming from the intake side or the exhaust? An ignition miss will send raw fuel into the exhaust, which shows as lean on the WB.

You mention having 54# injectors, do you mean 55#? Do you have any records to verify that the MAF software calls for the 55# injectors? How do you have the FQS set?
Assuming the 55# injectors are correct for your setup, it tells me that your system is probably the older version (pre 2007 (pre V-FLEX & V-MAF+). Does your system have a MAP sensor?

Do you have a PiggyBack on the car?

A few simple tests I would try first:
- Power the MAF directly from the battery.
- Disconnect the MAF. Note how it affects the issue. (This test will affect the Idle and light cruise, we are just interested in the issue areas).

Once we have a bit more focused details of the conditions, we can hone in on the cause.

moalaska

Hey john
Thanks for always chiming in to help out rennlisters
it seems to do this whether there is enough load to build boost or not
If i give it just enough throttle to creep past 3000, it still seems to go lean. Popping is backfire seems like exhaust and it will do that if i hammer it down when it is in "this mode"

Very well could be an ignition miss if i have bad wires.

I mean 55# the siemens injectors
Fqs set to 0
Older set up
Other fqs settings seem to correlate to factory fqs settings, add fuel subtract fuelall show corresponding differences in wideband
No map no piggy

Ran wires directly from pos and negative to maf to zero out griund/ power issues

I remember unplugging maf i can't remember what the result was but i do remember it either shut off or affected things very negatively

Thanks.

fast951

Good data.
Popping from exhaust makes me think it's rich. Popping from intake is lean.
Something to keep in mind.

Sorry, I meant disconnect TPS not MAF. Let us know how it affects the issue.

Do you have access to a different KLR chip?

Did you verify chipboard is fully seated in DME socket?

moalaska

Disconnected tps other day as well
Idle goes up
Microswitch works
dont remember what else that was a couple days ago.
Did open it up clean tracks for potentiometer

Opened dme inspected pulled chipboard reseated
Don't have access to another klr. I could crack it open and resolder

Jfwiw black wire from maf is ground?
Original instructions said to wire it to original afm harnes wire.
Im assuming you revised wiring scheme for ground as everything ive read shows people grounding it to turbo water pump. Either that or i grounded wrong wire lol.

fast951

Perform a test; drive with TPS disconnected just to see how it affects the issue. Obviously if it starts to lean out badly, abort.

Black wire is ground, connecting it to GND wire on harness is fine. We added another engine/Chassis ground. Instructions have been revised, best to follow what came with the kit.

moalaska

Will perform drive test this afternoon. It did seem like tps symptoms but i did test per clarks a few months back.

moalaska

I did some diagnostic testing today

i get 12 volts at pin 18 and 35 on dme plug with dme relay jumpered
12V pin 1 with key on
pin 34 and 33 resistance 34 ohms for idle valve
temp sensor pin 8k ohms guessing tempurature is between 16 and 20f
Pin 22 has 3.6 volts

Pin 28 has continuity to ground
Pin24 has no continuity to ground
This is oxy sensor, i believe its supposed to have continuity to ground

Pin 2 at klr gets 1.5 ohms at idle clarks says 0 to 10 for tps
for the potentiometer i get 578 ohms at idle climbs up to about 3k ohms right before full, then infinite

NCLA951

I don't think the TPS should go infinite, I think 4700 tops?

moalaska

Yeah something isn't right. Ill double check tomorrow make sure my multimeter wasn't set funny. Ill check at klr and at tps again. Even if it is going infinite at near full throttle i don't think that would have caused my light throttle stumbling. I can definitely see how it would cause full throttle confusion in the dme. I didn't test injector circuit yet either but i know unplugging them one at time indicates they are all working.

Tom M'Guinn

For what it's worth, injectors can be funny little creatures. I once helped a friend who had a brand new injector that seemed to work, but he was getting stumbling under load. He sent the injector to Witch Hunter for testing, and they said it was good. He finally replaced the injectors one at a time, and one proved to be bad. It would work fine up to a certain pulse rate, then become unpredictable.

Here's a thread about it:
https://rennlist.com/forums/944-turb...em-solved.html

Not saying that's your issue, but one more thing to consider...

moalaska

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Ok tested tps again, reads smoothly from 500 ohms idle to 4200 full. My meter was moving decimal over automatically when it reached 3000 hence the brief OL reading. Changed setting and all checked out.

I have a local place that can flow test at different pulse rates and ultrisonically clean my injectors for less than 150 bucks. Might be worth it.

Ordered a set of 10mm magnecor spark wires.
So maybe a bad injector or bad wires, they we're originals. Resistances and continuity checked out on all wires and end plug boots, the boots are all close to 3k ohms but one wire/ boot connection has some good corrosion on it.

Also here is a pic of my Microswitch i found at local electronics supplier, 3 dollars is allot cheaper than sourcing another tps.

Humboldtgrin

Are you sure you haven't damaged the two injector drivers in the DME due to using low impedance injectors?those are 2.2 ohm I think and stock are 4.5 ohms(turbo only). And that plug wire looks like it's done. It could very well be just replace your wires. And install 1 ohm resistors (two total) for each injector driver if you haven't or you WILL damage the drivers. The injectors are batch fire. Clarks garage has an excellent write up on the resistors if you haven't read up on them. I would pop apart the DME and KLR to make sure there not corroded as well. Were you ever able to test fuel pressure? Get a fuel pressure test kit from harbor fright. Or open another bank account for expensive tools if you go that route, separate from your living account and car parts/service account.
BTW I have a spare KLR if you want to see if that helps. But you have to become a member to enjoy these benifits. It just the way to go.

moalaska

I have fuel pressure guage on pressure regulator just can't test while driving. Dme looks good inside and i resoldered it. Don't know about klr maybe ill pop that apart tomorrow.