moalaska

The thing is that the old one did the same thing. I checked the ohms on new, a little higher but its the updated porsche part. Bypassing klr on list.

Tom M'Guinn

Just saw your spark plug video. Looks like those are Magnecor wires, and it looks like the boots are arcing. Magnecor wires are susceptible to boot failures (search here for examples). I once had a brand new out of the box set that created a nasty misfire. I still use them because they work with my MSD ignition, but you really have to be careful with them. I'd replace those with factory wires before touching another thing on the car. No guarantees, but there's a reasonably good chance that's your issue.

Tom M'Guinn

Pull the connector and plug the port on the I/c pipe and intake -- that will tell you if it's the issue or not...

moalaska

spark plug wires brand new Magnecor 10mm. Could be the spark found it easier to jump through the boot instead of traveling15 feet through a jumper cable.
i made an inconclusive video of me bypassing the idle valve somewhat. At one point one it reaches stoich, i tighten the valve some and afrs go down to 13, loosen up valve and they go up. After that they are in 16's. Don't know if tightening the valve/bypassing the idle valve isx what caused it to go down, or just coinxidenve and some other problem.

https://youtu.be/cJavuIMhq-A

https://m.youtube.com/watch?v=cJavuIMhq-A&feature=youtu.be

fast951

I have not been following the progress on your project in full, however I did see the video you just posted. A few observations:

- You state that fuel pressure is 45psi with engine running. This is higher than it should be. Fuel pressure should be 3bar (43.5psi) static. With engine running, under vacuum when idling, the gauge should read lower. More around 38-40psi. Best to set it with engine off.
Based on what I saw, your cold start and closed loop are functioning as expected. However, the AFRs are on the lean side.

- When you open/close the valve, emulating the ICV, have you monitored your vacuum? The air going into the engine is after the MAF, so it's metered. However you are altering the vacuum which affects the fuel pressure, which translates to a change in AFRs (less vacuum = higher fuel pressure = richer AFRs).

Back to the lean issue. I'm believe you are not the original owner of the MAF kit, hopefully you did get the FQS and chipboard images documents along with it. They are needed to determine a few key issues that affects the running conditions.

- Are you sure your setup calls for 55# injectors?
- Are you selecting the proper image on the chipboard? Some customers requested support to multiple injectors, so the chipboard will have various images.
- How do you have the FQS set, which position? Did you try adding fuel via FQS to see how it behaves?
- Do you know the condition on the injectors? All flowing equally?
- In the past, we have seen faulty injectors shut down as soon as you start building boost. Keep this in mind.

moalaska

Ok so ive adjusted pressure with engine off pump jumpered. Does a properly functioning o2 sensor compensate for fuel pressure variations, example if i turn pressure up should i see it go richer or does o2 sensor see this and signal dme to turn diwn injector pulses etc?

You can see that right before it appears to go from open loop to closed loop, afrs are close to stoich, then im guessing that's When it switches and goes lean.

I do not have settings instructions for maf, seller assured me that it was set up for a stock 2.5 and that with the dip switches in where they were that those are the proper maps. Recieved the semend dekas with set up, 55#.

I will do some different tests today

Unplug o2 sensor
Fqs settings
Test maf voltage
Pressure test intake
Noid light
Unplug injectors and see if afr difference is consistent

I have had this setup working properly before, so i know you still ask what changed since then.

Had fouling issue from cold starts and bad plugs

Changed plugs
Rebuilt harness connectors were horrible
cold weather makes noticable differences with sketchy components especially bad electrical connections

Will take videos and post results

F18Rep

Many good ideas here and and I usually ignore the minor ICV leaks but I did one last week that changed my mind. Seems similar... high idle, could not adjust it down. Ok in traffic at low RPMs except when cold, then it would cough under load. Boost was erratic and stumbling.

Pressure tested intake, I could not even get up to .5bar (using the DME/KLR test plan) - big leak. Pinched hose to AOS - still big leak. Pulled intake, put on a block-off plate on back of TB and two 1/2" rod stubs to block the hoses between the intake runners. Several small leaks found with soapy water (fixed) but the ICV was blowing big bubbles at both ends. Swapped in a salvaged ICV and voila; no leaks.

PS... I have the ICV apart, nothing obviously wrong so I might try to change the orings. What the hell, ICVs are not cheap. ... Bruce

moalaska

Ok i checked a couple things out.

Afr is unsteady between 16.5 and 17.5.

Unhooked o2 during running. Little difference if none.

Cranked fuel pressure up to 3.5. Seemed to be less lean but still lean

Makeshift idle valve adjustment no effect

Unhooking injectors one at a time all produce about the same afr difference one isnt drastically more or less than others

Took filter off maf, seemed to make small difference

Fqs setting, +3% and +6 fuel settings are functional, +3 got it to about 16, +6 to high 14s

Pressure test intake, found a vacuum hose that was fairly loose and hissing, swapped hose with tighter hose

Found slightly loose hose attached to banjo fitting for boost controller, tightened
Note, rubber gets very hard when its zero degrees outside and doesn't seal well, exagerates leaks

Idle valve sounds like its leaking

I don't know if the leaks would be enough to make that much of difference to go lean to 17, didn't test After fixed leaks

Ok would a missignaling temp sensor cause a lean condition?

Thoughts, either my fuel pressure guage is wrong, maf output is low telling dme less air is going through, something seriously wrong with dme, all 4 of my injectors are consistently plugged, or something else i haven't thought of yet.
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Stephencs601

Do you have a rev or boost limiter? Have you adjusted the FQS yet.

odonnell

Have you eliminated the possibility of the fuel pump going out? It might be able to cope at idle and low load but might be struggling when you need the most fuel flow. A comprehensive test would be to log fuel pressure during a drive and see if pressure starts to drop off. That would tell you if this is a fuel issue, or an air issue.

fast951

A vacuum leak will cause it to go lean at idle/no-low load. And will cause it to run rich under boost.

Where did you get the +/-3 and +6% FQS settings. I don't remember ever using these numbers on a chipboard image. Regardless, just note which FQS positiin adds or subtracts fuel.

I could not tell from the video if your FPR is vacuum referenced. Could not see a vacuum line going to it. Can you confirm it has vacuum?

Have you tested your BOV to make sure it's not leaking?

What do you mean by "not having a temp sensor"?

moalaska

I just replaced the fuel pump, plus if I can crank the fuel pressure way up to 60 plus psi at idle that should eliminate fuel pump being culprit, at least at idle. I understand what you area saying though.

moalaska

I know you do different things with your chipboard, however if I go off the standard fqs settings they all seem to correspond, position 0 is normal, position 1 is +3% fuel, position 2 -3%, position 3 +6% and so on. This is an ancient maf setup.

I pressure tested system yesterday i can plug bov to see if anything changes. That has been replaced as well.

fpr is rising rate vacuum referenced.

I was saying would an improperly working dme temp sensor cause lean condition even when warmed up?

fast951

A bad Eng Temp sensor will screw up the AFRs, especially during the cold engine warm up cycle.
However, based on your video, it appears that the eng temp is working as AFRs start as being rich, then lean out as the engine warms up.

BTW at idle 850 +/-40 RPM, on a hot engine, your MAF voltage should be around 0.6V (checked at DME pin #7). I would compare the signal at MAF sensor & at DME. A voltage drop in the line will cause a lean condition.

moalaska

Ok cleaned the maf sensor and tightened up some loose vacuum lines. I didn't measure maf voltage at dme i found a location on the maf to measure. Unless there is a bad connection at the maf or my solder joint is bad, i would think measuring there is ok as I ran all new wires to the dme. At first when warming up voltage was around .7, once it got warm it dropped down to about .6. Afrs were high 14 low 15. Im hoping its not an intermittent issue. So maybe hopefully I got the idleing afr straightened out, i haven't ran it under load or higher rpms yet one thing at a time.