- Thread starter
- #381
I ordered a new oem booster for the 93-97 model years, since the 91-92 is not longer available. I had upgraded the axles with later 80 e-locker, FF, Disc brake axles, so I probably needed this anyway.
Build US Spec. February 1990 Poverty 80 2uz/h151f swap
- Thread starter Tank5
- Start date
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You should probably up grade to a bigger Master cylinder while your in there. Many go to the T-100 one ton. Sorry I don't have a part # for you.
This? 4720134031
Mr T. still makes/sells this
Mr T. still makes/sells this
- Thread starter
- #384
Thanks for the idea @Broski and @cruiser lab. I have a brand be Master in there already. I did it when swapping the new axles in with disc brakes. I cannot recall what I swapped in but I think I bought it from City Racer. I am going to run it for box. I need to get this thing driving I get too crazy. The tires and wheels were a splurge when I thought I was going to have it driving soon. Maybe I will.
To be clear... I don't know if that is the correct part # that @Broski mentioned. I just quickly went on to Partsouq and found that.
@Tank5 you got this!!! Hang in there. Sense it is close!
Good to hear that you can rule out the MAF tube diameter as being an issue - although that would have been an easy fix. This is great info for others doing the same swap in the future.
I would keep at it because you must be close to figuring it out. A lot of people have given great advice in your thread for possible causes and if it were me, I would review all the possible culprits suggested and ensure I checked them off starting with simple then moving to complex.
Have you considered reaching out to @2001LC to see if he can help you out? He seems to be the guru on 100 series/2uz and is located in Colorado.
If you plug brake booster vac line, does fuel/air ratios improve?
- Thread starter
- #389
They do improve but they still aren’t good, so I am looking for another leak or issue.
Because the Long Term and Short Term ratios are offset, that's really promising.
If you drive it, it looks like you'll be <10 on them.
-Rob
- Thread starter
- #391
I was going to wait to install the new booster but I may go for a short drive ahead of time.
My understanding is that if the L/S FT added together are within 7% that is generally acceptable. Correct me if I said that wrong. I feel like I am making progress.
- Thread starter
- #393
I test drove it again tonight. With the booster vacuum port plugged at the planum and no other changes. It is still in limp mode. Under load the fuel trims return to around 30%. It is gutless, stumbles, and doesn’t have any pedal response except really slow and delayed.
These are the FTs idling I the garage before the drive.
These are trims at the end of my driveway when I stopped to set up the computer.
These are the fuel trims under load
These are the FTs idling I the garage before the drive.
These are trims at the end of my driveway when I stopped to set up the computer.
These are the fuel trims under load
Is throttle plate on intake electric or cable actuated? If electric can someone watch the throttle open operation as you press the pedal? Reason I mention this is you state throttle response is slow and delayed.
- Thread starter
- #395
I did have an issue with the throttle not opening up beyond about 1/3. I just got the harness and ecu back from the builder who fixed the issue. I used my phone to record the throttle plate reaction while I worked the pedal. It is opening all the way now.
Likely already said, but what did you do to intercept the original sensor for traction control? In an 08 GX, the engine cuts power when it senses differential rotation in the driveline. I noticed that even slop in the driveshaft would trigger engine cut when shifting from reverse to drive. Maybe the ECU is looking for stability control computer input.
- Thread starter
- #397
I can’t say that I know for sure. I sent the harness and ecu off to have them programmed built into a stand alone unit. Any systems that I don’t need to run the engine in my application were deleted or bypassed. How the traction control was addressed I cannot say.
I think it's an intermittent MAF issue due to a bad connection. In your first pic you have a more reasonable idle MAF reading (4.45 g/sec), LTFTs of around +20%, and STFTs of around -12%. That means your MAF, at the time of the screenshot, is working better and the computer is making the short term trims very negative to get to the commanded AFR. On your driving screenshots, your fuel trims are +30%, meaning the computer thinks much less air is coming in than actually is, and is adding a ton of fuel to get to the commanded AFR. A plausible scenario is that driving jostles the MAF harness causing a the poor connection to develop. Either way, getting the MAF wiring 100% sorted important if you want to have a rig that runs well.
- Thread starter
- #399
I
I did order what I need to replace the plug but that stuff won’t arrive until next week. I am going to check the plugs at the ECU as well.
I did try capping some of the other vacuum ports but didn’t get any different results.
I do appreciate the help.
I appreciate the diagnosis. I agree the issue could be in the MAF circuit as I had issues with it before but then I had trouble codes for the MAF that went away after the plug was replaced. If it is intermittent that would explain why my earlier circuit tests were ok.
I did order what I need to replace the plug but that stuff won’t arrive until next week. I am going to check the plugs at the ECU as well.
I did try capping some of the other vacuum ports but didn’t get any different results.
I do appreciate the help.
Are your knock sensors good?