the flyin' scotsman

Thx for the vacuum confirmation Ole.

I double checked the TPS with Theos diag system................all good at idle, off idle and WFO. To be absolutely sure I disconnected the new throttle cable, no diff. to the hi idle.

Its been raining for +30hrs here

the flyin' scotsman

Its not as pretty as Dwayne's idea but it should work............2 plumbing and one tractor store later

Tampa 928s

Search is not my friend where did you find this post?

Might also test the vacuum with some smoke. I suggested on RM that you could use R/C airplane smoke pack in conjunction with the intake contraption Dwayne wrote about using Home Depot plumbing parts to push smoke into the intake to mimic the VacuTech machines that some shops use.

Calgary Ole

Just make sure to add 1 HG for every 1000'

Jerome Craig

PM sent

Stromius

My post on RM : http://reutterwerk.com/forums/showthread.php?t=21383

Figured if you light off one of these (http://www.rcuniverse.com/magazine/a...article_id=215) in a scraficial brake fluid jar and pipe this into the intake. Since it's non toxic and assuming no harm done, you'd see vacuum issues pretty easily. Maybe I'm just back from the crackhouse but wouldn't this give you the visual telltales?

WallyP

At $10 for four minutes of smoke, it better show the leaks pretty damn fast!

Stromius

Well at least it would be in the theme of MacGyver to rig something up rather than buy a VacuTech

the flyin' scotsman

I tried to pressurize the intake last night with my version of Dwaynes intake tool.............wont fit

The MAF is bigger than 3" but fits perfectly in the lower air filter box. IIRC Dwaynes car is an '87...........did the MAFs change?

BTW...........I checked the vacuum at the flappy valve switch and have the same values as the front fuel damper 14 in Hg. Adding 4" to adjust for altitude we have 18 in Hg.

I ask again, will a bad Temp II affect the idle this badly? I can swap the S4 T2 sensor into the GT this morning.

Stromius

I thought temp2 was failure only resulted in rich running condition versus higher.

Interesting your MAF is not fitting the 3" adapter. Maybe a little vaseline to help? My 88 MAF is stock and fit.

Does the temp2 test correctly with a MM?
The proper Temp Sensor II resistance measurements are:

0 C / 32 F: 4.4k to 6.0k Ohms

15 - 30 C / 59 - 86 F: 1.4k to 3.6k Ohms

40 C / 104 F: 0.9 to 1.3k Ohm

60 C / 140 F: 480 to 720 Ohms

80 C / 176 F: 250 to 390 Ohm

How about the MAF wiring? Any chance the wires have exposed strands and causing your idle woes? Pic of my MAF plug wiring. Wouldn't hurt to check the MAF wiring either. I fixed both with my intake R&R.

John Speake

The MAF is the same diameter from the 84 Euro S through to the last GTS.....

I don't think a faulty temp 2 would give the effect you have, or a faulty MAF, but ....... does your diagnostic tester give actual values of Temp 2 ?

the flyin' scotsman

I'll try the pressure tool again on the MAF............unless the rubber adapter is stamped wrong!

John........the diagnostic tester provides real time actual values of the Temp 2 through the LH and EZK tests. As mentioned the tester displayed 1 fault code on each ecu ...........Temp 2.

The tester also provides real time MAF values which appear to be within spec.

the flyin' scotsman

I'm going to throw this out there also so we have all the cards on the table:

The car is a '90 GT originally configured for the Japanese market. Prior to coming to Canada the car had the a/c compressor bracket welded and I assume that there was a small engine fire, perhaps sparked by the welding?. The engine wiring harness is brittle and when I had the intake off the knock sensors and hall sensor connectors were found destroyed thankfully at the sensor side. The CPS connector was damaged also but on both the sensor and harness ends. The sensor was replaced and also the harness connector from a donor harness (cheers Mike B).

I share this as theres potentially other wiring issues that I haven't found yet but have a hard time understanding how they'd affect the idle.

John Speake

OK, that's good on the diag tester. What was the temp 2 fault description ?

the flyin' scotsman

The fault codes were found while running LH and EZK analysis respectively.

For the LH its test point 4 which WSM ref page D24-14

For the EZK its test point 3 which WSM ref page D28-7

There's no further description on the tester but I'm inclined to do a manual resistance test while moving the wiring. As both cars are cold I could swap the sensors.