Gawynz Manche Thread

Gawynz

Active Member
Location
Ogden, UT
Thanks, I worked on it tonight, pulled the O2 sensor relay and checked it out powered and unpowered and it works as it should, checked the other three while I was there and they're all good.

I think I may have found a problem though, hopefully THE problem. Resistance from the harness ground lug on the dip stick stud to the battery ground is 0 ohms, so I have a good connection across that stud. Between the ground pin on the MAP sensor connector and the dip stick stud I have 50.4 ohms of resistance. I'm thinking I have a bad ground connection in the harness between the MAP and the stud ground connection. Could that much resistance be throwing things off?
 

Gawynz

Active Member
Location
Ogden, UT
Disregard the previous post, I just didn't understand what I was measuring across.

Summary of the work the past couple days:
  • Started by pulling the harness apart and checking grounds/crimps, everything looked good, it's at this point I realized my mistake in the question from the previous post.
  • I tested the MAP sensor, the sensor that was in it was not consistent in voltage response when vacuum was applied. I had another MAP sensor laying around and it tested good so I put it in.
  • The vacuum tube from the intake to the MAP sensor was broke a while ago, to fix it when I was just trying to get the engine running I aligned the two halves and connected them with heat shrink. It worked, but I also wonder because the two ends had a small gap the heat shrink pulled in under vacuum and choked it, that said it would still have vacuum just a bit of a delay I'd think. You can't buy those tubes anymore so I made one out of some brake line, it worked great.
1711318437739.png
  • Thoroughly cleaned the ground and connectors on the dip stick stud.
  • Adjusted the butterfly throttle body set screw to be correct.
  • Tested and adjusted the TPS to be in spec (wasn't too far out but it was out).
  • Pulled the IAT and it was absolutely filthy, I can't believe I hadn't checked this prior. Cleaned it up, retested and it's good, reinstalled.
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  • While I was at it w/ electrical I chased down the short to my aux fan, the crimp for the ground was pulled apart and the positive was barely hanging on, recrimped and it seems to work now, though I haven't got it hot enough to auto turn on. Also checked that the aux fan relay was good.
Today I drove it for ~1hr and it's never ran better, I was honestly surprised. The other surprise is it ran cool as a cucumber, in the past it'd get up to 200-210 just idling for a while, when I drove it around the other day it got up to 230, I had the same issue in SRS. One of the things above seemed to make a big difference (my guess is the big hitter was the MAP and MAP tube), I think it was running hot because it was running rich and I know I'm failing emissions because it was running rich. Today driving around it stayed aroudn 190 the entire time.

Anyway, I plan to try again on emissions early this week, fingers crossed.
 

Gawynz

Active Member
Location
Ogden, UT
Your "upgrade" injectors are likely bigger/higher flow, yes? You don't think they are at least contributing to your rich/high CO issue?

They are Bosch injector part number 0280 150 943. Renix stock is 19lb/hr at 39psi where these are 19lb/hr at 36psi so they're close (but leaning in the direction of rich), the only real "upgrade" is that these are four hole injectors. I agree though, they may be a cause, I just didn't want to spend the $ before I did emissions again. If I fail emissions this next go around I'll probably go back to stock.
 

Gawynz

Active Member
Location
Ogden, UT
Failed way worse this time around :mad:
1711548697980.png

After further research, some say the injectors I have in it are good for the HO 4.0 but for the Renix the Bosch 0280 155 746 are the best/correct; specs are 4 hole, 19.9lb/hr @ 43.5psi. I pulled the injectors last night, new ones are on order. I also pulled the throttle body and thoroughly cleaned it as well as the intake air controller, new gasket also on order. During reassembly I'll reset the butterfly valve and TPS. I'm running out of options...

I'm also still getting oil into my air box via the red arrow line below. The entire vacuum harness is new under the hood. the blue arrow line should and does pull vacuum and is supposed to pull vapors out the valve cover and burn them. For some reason though oil is going the wrong way down the red line and into my air box. It was really bad beforeI changed all the vacuum lines, the blue line was completely blocked. Anyway it seems to be functioning as it should in this circuit but I'm still getting a small amount of oil going the wrong way and into the air box.
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Herzog

somewhat damaged
Admin
Location
Wyoming
That blow by is pretty common. I've added a catch can to my 4.0L in the buggy because it was drenching my filter after a while. The PCV cleanout helps a ton to keep the pressure down but I've never been able to fully solve it, but I also didn't try very hard.
 

Trate D

Well-Known Member
I am running the Volvo injectors in mine and never had an issue. I pass emissions with ease every year. I’ll try to find the part number and specs for the ones I used when I get a minute. I also did the cruiser mod to the valve cover and had slightly less oil in airbox. But like @Herzog said the final fix (band-aide) was a catch can.
 

bryson

RME Resident Ninja
Supporting Member
Location
West Jordan
The blowby that is coming out of your crankcase and being introduced back through the intake could also be contributing to your high CO emissions readings. Some blowby is fairly normal, but a lot of it means internal engine wear beyond ideal limits (piston rings usually). A catch can and maybe venting it externally rather than back into the intake could help. The external vent probably isn't emissions legal. :spork:
 

Gawynz

Active Member
Location
Ogden, UT
I ran a warm compression test a few months ago, it was on the lower end but "OK" per the spec. This is my fear though that the problem isn't as simple as what I've been trying.
 
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