Running Super Rich. Correct maf sensor?? - Page 2

apachechef · 02-09-2021, 07:57 PM

follow culberro's line. If you used injectors from a turbo 740 in your car, without adding a resistor pack to your harness, you have fried injector drivers in ECU.
this will cause a rich state, very rich.

Sounds like you don't know about the difference between high res and low res injectors if you just know the color, which is not enough to tell.

don't swap in and ruin another ECU until you clear up and rule out this potential f up.

apachechef · 02-09-2021, 08:04 PM

Quote:

Originally Posted by culberro

Nope, but the sensor is near the gauge one. You're looking for a sensor under the intake that has an injector style connector on it. The body will be black plastic and brass.

it is possible to mistakenly swap I think the temp sensor, knock sensor, and perhaps the idle air valve and maybe cold start injector? have similar Bosch 2 wire plugs. Don't recall exact details, but check out this as a potential screw up too. the wire harness should fit as before, without "stretched" or weird routing. ultimately, check the harness colors to diagram to confirm

culberro · 02-09-2021, 08:21 PM

Quote:

Originally Posted by apachechef

it is possible to mistakenly swap I think the temp sensor, knock sensor, and perhaps the idle air valve and maybe cold start injector? have similar Bosch 2 wire plugs. Don't recall exact details, but check out this as a potential screw up too. the wire harness should fit as before, without "stretched" or weird routing. ultimately, check the harness colors to diagram to confirm

Definitely a possibility. I did that exact thing on my first lh2.4 swap

Cwazywazy · 02-09-2021, 08:37 PM

Quote:

Originally Posted by abelbushey

I have a set of yellow/ cream injectors.

These? Are you using a resistor pack or no?

abelbushey · 02-09-2021, 08:49 PM

Quote:

Originally Posted by culberro

This is very informative....

Yeahhhh. When I bought the car it came with a 95 percent complete turbo swap. Those were the injectors. I believe they came off a 850 but I could be mistaken. Next time I'm by the car I will see if there is a number on them. Als

abelbushey · 02-09-2021, 08:52 PM

Quote:

Originally Posted by Cwazywazy

These? Are you using a resistor pack or no?

Those look like what I have except mine would be faded a bit and no I am not using a resistor pack. If I do need one, is there a link to another form that goes over it?

apachechef · 02-09-2021, 09:07 PM

Quote:

Originally Posted by culberro

Definitely a possibility. I did that exact thing on my first lh2.4 swap

Only a moron would screw up the high-low res thing on their first swap

yeah, I've done both these f'ups

Cwazywazy · 02-09-2021, 09:07 PM

Quote:

Originally Posted by abelbushey

Those look like what I have except mine would be faded a bit and no I am not using a resistor pack. If I do need one, is there a link to another form that goes over it?

I believe those should work without a resistor pack?

apachechef · 02-09-2021, 09:09 PM

Quote:

Originally Posted by abelbushey

Those look like what I have except mine would be faded a bit and no I am not using a resistor pack. If I do need one, is there a link to another form that goes over it?

add turbobricks to your google searches, and you will find all you need

abelbushey · 02-09-2021, 09:16 PM

Quote:

Originally Posted by Cwazywazy

I believe those should work without a resistor pack?

I assume if they needed a resistor pack and didn't have one the car wouldn't run at all.

culberro · 02-09-2021, 10:06 PM

Quote:

Originally Posted by apachechef

Only a moron would screw up the high-low res thing on their first swap

yeah, I've done both these f'ups

I had the resistor pack, but I didn't label the 2-pin JPT sections of the harness. It doesn't run well when those are all mixed up.

culberro · 02-09-2021, 10:08 PM

Quote:

Originally Posted by abelbushey

I assume if they needed a resistor pack and didn't have one the car wouldn't run at all.

It would run exactly as you have described, which is why I asked.

If you have thin plastic injectors, they are probably high-z (high resistance, around 13-15 ohms), and you probably dodged that bullet.
If they have a fat black or silver body and a plastic part on top, you may have low-z (low resistance, ~3ohms).

shoestring · 02-10-2021, 11:55 AM

Quote:

Originally Posted by Fa182

The NA engines don't have a resistor pack? Unless I misread what you're saying.

No they do not. The resistance is in the injector.

shoestring · 02-10-2021, 12:11 PM

Is this rich condition and chugging at part throttle, WOT, etc? Do you have an exhaust leak pre O2 that's pulling a bunch of air?

2manyturbos · 02-10-2021, 03:22 PM

I would not at all be surprised if the problem is the 560 ECU. Those are notorious for failing, resulting in all kinds of issues, including rich conditions. I have not encountered one in 15+ years because they were always replaced with a later version 939 EGR Turbo ECU. See if you can borrow a known good 939, 937, 954, 967 ECU to check whether that is the problem.

redblockpowered · 02-10-2021, 04:14 PM

I have a functional 560 sitting right here, also. Looks like it was repaired under warranty.

dl242gt · 02-10-2021, 04:23 PM

Quote:

Originally Posted by abelbushey

Is this the same sensor that will send a signal to the gage?

No, it is the sensor for each computer. It is actually a dual sensor with a signal readout to the EZK computer and the LH computer.

apachechef · 02-10-2021, 06:15 PM

Quote:

Originally Posted by 2manyturbos

I would not at all be surprised if the problem is the 560 ECU. Those are notorious for failing, resulting in all kinds of issues, including rich conditions. I have not encountered one in 15+ years because they were always replaced with a later version 939 EGR Turbo ECU. See if you can borrow a known good 939, 937, 954, 967 ECU to check whether that is the problem.

seriously OP, CHECK injectors by # BEFORE Assuming they are ok, as it will ruin the ECU too if inj are wrong

abelbushey · 02-10-2021, 11:10 PM

Quote:

Originally Posted by culberro

It would run exactly as you have described, which is why I asked.

If you have thin plastic injectors, they are probably high-z (high resistance, around 13-15 ohms), and you probably dodged that bullet.
If they have a fat black or silver body and a plastic part on top, you may have low-z (low resistance, ~3ohms).

They are definitely the thin plastic injectors. They look nothing like the short fat ones that came off the car. I will check the resistance of the injectors next time I'm by the car.

abelbushey · 02-10-2021, 11:12 PM

Quote:

Originally Posted by shoestring

Is this rich condition and chugging at part throttle, WOT, etc? Do you have an exhaust leak pre O2 that's pulling a bunch of air?

The car runs rich at every rpm. The car shutters a little under very light acceleration. At WOT it bucks/ chugs very badly and the afr gauge will max out rich.

abelbushey · 02-10-2021, 11:13 PM

Quote:

Originally Posted by apachechef

seriously OP, CHECK injectors by # BEFORE Assuming they are ok, as it will ruin the ECU too if inj are wrong

Foolish of me to assume they were correct

I bought the car with a good pile of turbo parts but I never thought to check on the injector numbers.

Fa182 · 02-11-2021, 05:28 AM

Quote:

Originally Posted by shoestring

No they do not. The resistance is in the injector.

Yes I know, I was just correcting what was said earlier

OP: Check resistance or number on injectors and compare with this table: http://users.erols.com/srweiss/tableifc.htm
NA 240 engines use hi-z injectors, Turbo engines use low-z (usually the black/green 0-280-150-804) with a resistor pack.

02-10-2021, 04:14 PM	#41
redblockpowered cone dodging dilettante Join Date: May 2015 Location: In bed, probably	I have a functional 560 sitting right here, also. Looks like it was repaired under warranty. __________________ 1993 944 B230FT/M90 thread here: http://forums.turbobricks.com/showthread.php?t=345277 2x 1991 245 B230F/M47 (LeMons car, street car) I sell chips for LH 2.4!

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02-10-2021, 12:11 PM	#39
shoestring Board Member Join Date: Jun 2009 Location: Swampscott, 01907	Is this rich condition and chugging at part throttle, WOT, etc? Do you have an exhaust leak pre O2 that's pulling a bunch of air?

02-10-2021, 03:22 PM	#40
2manyturbos Moderator Join Date: Mar 2003 Location: Monroe, OR USA	I would not at all be surprised if the problem is the 560 ECU. Those are notorious for failing, resulting in all kinds of issues, including rich conditions. I have not encountered one in 15+ years because they were always replaced with a later version 939 EGR Turbo ECU. See if you can borrow a known good 939, 937, 954, 967 ECU to check whether that is the problem.