What are the chances my MIL is burnt out?

[Greg Corcoran]

I was hoping the fact it changed my symptoms was a clue that would help someone better pinpoint my issue. I'm completely stumped.

So based on the data thus far:
SHO surges in open loop, from cold start, between 3- 4,000 rpm, after 2-3 miles of driving no more surging, so closed loop OK.
Above 4000 rpm not surging
Tach reading does not changes while this is going on
No surging on warm or hot start
As near as I can tell looking in through the glovebox and feeling around there is no chip in the J3 port of the computer
Performing the upper 60K had no impact even though all the plug wells were full of oil
Running with CID disconnected has no impact
Disconnecting the CANP and plugging the lines changes the symptoms a bit, but they are still there
Injectors, MAF and IAC cleaning had no impact on surging but improved cold starts
Maybe a red herring, but warm starts after sitting 10 - 45 minutes are tough - long cranks and when finally starts it's slow, and "sneaks up" on a normal idle speed
Codes in KOEO are 111 and 111
Codes in KOER are 111 and 111

Therefore:
One of the inputs or outputs for open loop has a hardware problem, and the EEC can't account for it in open loop until the secondaries open and it goes to a different table in the EEC.
CANP has an impact, but it is not the root cause, CANP adds mostly air and trace fuel vapor, so something air related in open loop...

What am I left with, swapping out open loop sensors?
MAF, TPS, BAP, ACT, CPS, ECT probably in that order?
Or swapping out devices - Injectors, DIS, coil pack, probably in that order?

 

[Greg Corcoran]

DONE!
I swapped the stock MAF for the 80mm MAF from my deceased '92, and disconnected and cleaned the TPS and BAP connectors. reset the computer. There was some lovely jade green oxidation on the middle tab(of 3) of TPS connector.

Cured my surge! Three days and no cold/open loop surge. (also set code 173 once when it switched to closed loop about 2 miles from my house, it cleared MIL after a few minutes but stayed in continuous memory). How do I go rich with more air from the bigger MAF?!?? I'm sensing a set of injectors in my future...

Warm starts like after 45 - 60 minutes still long cranking affairs.

Quick question - can I just buy three for the rear bank, or is the accepted practice to buy all 6? In reality I only need 1 prolly, but which one?

I'm going to put the old MAF back in and see if the problem returns or if it was the TPS corrosion

I'm going to start a new thread for my CCRM, it's also acting up and can't seem to find a known good one to swap in...

 

[zoomlater]

When you previously had the 80mm MAF installed on your 92, did you have a LPM or something else to adjust for the bigger MAF

 

[Greg Corcoran]

When you previously had the 80mm MAF installed on your 92, did you have a LPM or something else to adjust for the bigger MAF

Gonna plead CRS (can't remember sh..). I want to say MAF was calibrated to work with stock injectors. But - Having said that, I do have a box of used injectors on the shelf that say stock SHO 3.0L, in my handwriting, so at one of the 60Ks I must have upgraded or at least replaced, I just don't remember...
I know I never had an LPM or other chip because I didn't think I'd ever pass Colorado emissions with one, based on local lore.

 

[zoomlater]

Not sure which 80mm MAF you have, if it is a Pro M, then you are probably okay without the chip. If it is the Lincoln one, then a LPM or tuner is needed

http://wikisho.com/wiki/MAF_Sensors

have you looked at this thread

http://www.shoforum.com/index.php?threads/ircm-ccrm-details.75065/#post-739231

 

[Greg Corcoran]

Not sure which 80mm MAF you have, if it is a Pro M, then you are probably okay without the chip.

Thanks zoomlater, It's for a Ford p/n on the sensor. Here's its mug shot. Btw I get a bit less than 80mm when I just mic'd it. More like 72mm. Told you I have CRS...

 

[Greg Corcoran]

I'm going to put the old MAF back in and see if the problem returns or if it was the TPS corrosion

It's baaaack! I put the factory MAF back in and the surging returned. Not sure if I want to swap electronics between MAFs to further narrow down root cause, I'm thinking not. I'll just go back to the aftermarket MAF that was on my old '92.
I used to have a CSHOC club email signature that had all the mods for the '92. If I can find it, it should clarify what aftermarket MAF I really have...

Now, since I corrected my stock/baseline performance, and I've begun the down the slippery slope with a MAF mod, I guess it's time to let the wild rumpus begin... I've ordered sub-frame connectors, equal length Y-pipe, and brake bias plugs from SHOSource I'll need a Wavetrac or Quaiffe once I've saved up...