thedoc1876

Hi guys.
I own a '88 coupe and one of the rear defrost wires that was soldered to the hatch window has broke off. I have tried soldering it and even used tin flux. Nothing I do will work on it. What do I need to use to attach it?
Also since I bought it the coolant temp reading on the dash has never worked. Always says low. I have replaced both sensors on the block. Still nothing. I pulled the ecm out and the po had spliced in a new wire directly from the ecm to the sensor on the pass. side of the engine block. The original yellow wire was spliced at the ecm. The yellow wire that goes into the harness under the dash wasn't spliced into the new wire so I tried that. It still doesn't give me a reading. Now after about 20 min. of driving the check engine light comes on. The car seems to run rich also. So i'm wondering if since there isn't a temp reading that the ecm is choking the car making it run rich?
Any help would be greatly appreciated. Thanks!

hcbph

Maybe something like this: http://www.frostfighter.com/index.htm

thedoc1876

Yup that looks like it will be perfect. Thanks!!


Also my car has the notorious blowing hot air all the time problem.
I have the replacement clip for the hot/cold door under the dash however that looks pretty tough to get into. anybody have a detailed way to replace it?

WVZR-1

You've mentioned much that isn't correct here so I'd think you sort it out in order of maybe importance.

1. Have the car scanned for the CEL codes and react to the "run" issues first. I suggested a scan because if you've multiple codes a scanner works much better than a manual check jumpering the ALDL (I think anyway so ..)

Do you have the FSM for the car?

There are no TEMP sender/sensor for ECM or TEMP GAUGE on the BLOCK.

The YELLOW that you mention at the right side of block isn't the CTS the ECM uses for signal. ECM - C10 CTS wire is YELLOW but it's information is from the CTS front of the intake. The sender in the RH Cylinder head should have a GREEN wire that is used for TEMP GAUGE in cluster. Look for maybe a GREEN wire dangling in the vicinity. A "dangling" disconnected GREEN I believe will give you what you see.

CTS for the ECM is front of intake below throttle body. Rear of RH cylinder head for temp gauge cluster.

The rear defrost I'd think of no importance at this time.

Kevova

Rear defroster bonding kit should be available at local parts store. The kit for tab should attach wire.

thedoc1876

Ah ok. I'm just going off of the "hack" job the P.O. must have done previously.
Thank you for your response. I will get started on it immediately.

thedoc1876

Ok I have found everything. The last question I have is where does the dark green wire run to from the water temp sensor. I'm just going to run a new one.

Cliff Harris

It goes to the instrument panel. It goes through C100-C2.

WVZR-1

I'd search this wire bundle looking for the DK GREEN before attempting to get into the C100. If you had trouble locating it in the bundle you might find it coming out of the C100 and just splice.




Here's C100 PIN-OUT Many struggle with the PIN-OUT orientation

Joe C

not sure where some of this thread is going, but addressing the broken defroster wiring tab, i did have success re-soldering mine. it's been around 15 years now, and i don't remember the details, but i seem to recall using a weller soldering iron with 60/40 rosin core, and i reattached it to the farthest or end solder pad. it appears that OE used some sort of conductive adhesive similar to the frostfighter link, and was attached between two solder pads.

kenmohr

me too

vetteman42

Had the same issue with my '91. Use the rosin core and iron as suggested above AND it helps if you have another set of hands. But, I didn't and managed on my own. I think the key is to heat up the wire first, you want it hot enough so when you press it to the tab with solder iron that solder will flow almost immediately. Once you get that flow of solder withdraw heat, but hold wire in place for a few seconds.

Cliff Harris

The braided copper is a very good heat conductor. It takes a LOT of heat to solder the wire to the braid. I used a 100W soldering iron and still had trouble getting it hot enough.

thedoc1876

It works perfectly now!!
Thank you so much for your detailed advice. Spot On!!