air temp sensor, & the rebuild is done & its running.., sort of

[livinez]

Finally got the 85 back together and on the road. Unfortunately my ignorance of all things TPI is now hindering me. My EZ Link tells me the air temp sensor is reading 203 degrees all the time. Changed the $7 sensor and no change. But did notice that the lead wire is also readily stocked and runs $60+ !! Hmmm,before I run out and purchase this beauty and get in the throwing money at my ignorance mode, I figured I'd post this on a Buddies PC and see what you all here at CAC think. (mines down for a week, nice timing!) Anyway the car doesnt come out of open loop. And the rich lean flag reads lean. Which isnt the case. sparkplugs read rich. Car doesnt like to idle when cold and will idle at different rpm's warm. Stumbles at opening throttle in lower R's but pulls better at higher rpms. In carberated cars I'd be leaning things out. I'm lost with TPI.
Gutted the cat and the air pump. Welded up the exhaust manifolds former air inlets, but otherwise its stone stock. Timing at 6 BTDC. Cleaned and flowed injectors out of a 93 from Witchhunter.
Will probably turn the car over to real mechanics if I dont solve my problems this weekend. I'm just a parts changer and rebuilder. Tuning has always been a shortcoming.
Willbe going through the archives and watching for your input in the meantime
Later, TC

 

[Ken]

When I first got mine running last year, we discovered the air inlet temperature was reading a constant -240° F. We finally traced it back to a defective, although brand-new, computer. The board must have had a short in it.

I read somewhere that the -240° temperature is the default reading when something goes amiss with the computer, or maybe the sensor too.

You'll get more feedback.

 

[livinez]

Things that make you go hmmm

Probably should have ordered the factory manuals while I was waiting for parts. Got a set off EBay for work trucks and they are NICE!!!!!
It did momentarily flash 94 degrees while I was monitoring it. But hasnt since. I hate running it so rich, dont want to wash the cylinders with new rings breaking in.

 

[Ken]

I hear ya.

 

[ErnieN85]

Same problem with my 85. I've swaped ECM's and the result was the same. most of gthe time mine reads 203 also! but I have had it report correctly. one of the problems with the 85 is thta the baud rate for data transfer is so slow that I really think that a lot of tghe time the information reported to the scan tool just isn't correct (skipped over maybe) as to the open vs closed loop I haven't seen closed loop yet! and all conditions (that I know of) have been met. coolant temp over 140. and run time over 3min. with the o2 sensor switching.

maybe if I get peeved enough I'll change over to a later ECM and see if that fixes it. however the car runs good and as far as I can see it would just be a lot of work. for not much gain. (for me)

 

[livinez]

Thx ErnieN

And everyone else. Finally got the PC fixed and DSL up and running so I could follow up here.
Not worrying about the high reading for now.
Replaced the IAC after finding it froze up when I went to check it. Fixed most of my problems. Along with finding a bad connector on a injector.
Still get trouble codes 52, 53 & 54. Will replace the fuel relay and the Maf relay as they are original and have read that they should be replaced occasionally.
Havent descreened the MAF yet or done the coolant bypass.
Exhaust note is kinda funky cool with the cat gutted.
Busy working and getting the rest of my life is some sort of order
Will follow up with the odd note with one of those trouble codes. Dont know what to think about the high voltage code. Dash says 13.2 stopped - 14.1 running. Multimeter concures.

Oh well. I'm just driving it! Use it to do estimates for a friends tree service.
Folks dont know what to think when a vette pulls up a smilin handsome:cool dude jumps out dressed like a logger!
I tell them the truth..., its my economy car!

Later, TC