Okay some run down on my car, my 1992 calypso notch was once a 4cyl but in 1998 was converted to a v8 using a 1988 donor car.
I've been trying to figure out why my wipers are stuck on all the time, my rpm gauge doesn't work in the cluster and neither does my horn.
I have replaced everything to do with this issue.
But recently I bought some parts off a guy and he said my fix is a 1990-93 airbag harness because it's a dual plug (plugs by wiper motor going into the car) and the 1988 was not a airbag car.
Now he has both a 1990 harness and the matching gauge cluster because I have a 4cyl cluster still (I didn't know there was a difference)
My question to you brilliant wizards on here, will this 1990 airbag harness work? He said it goes from the starter and RE-wires my whole dash.
You are on the wrong track. There is no difference in dash harnesses between 4 cyl and V8 cars, it's all in the computer harness which goes on the other side of the firewall. What you need is a 92.5 to 93 dash harness, and a 92.5 to 93 engine harness. That will fix all your issues. You will also need a V8 or 4cyl cluster out of a 91 to 93 car. A 90 is different. This stuff is all year specific, computer, dash and even body harnesses are all different. In 92.5 then moved the fuel pump relay out from under the driver's seat out to on the firewall next to the WOT cutout for a/c. Hope this helps.
The harness I picked up is from a 91 v8 and it's different then the one I have. The one I have has two plugs coming out from the firewall??? Yet the new 91 harness has only one plug.
I think I may just source a 92 v8 parts car lol
What a nightmare.
Also heard if you use a 4cyl cluster with a v8 harness it will read 1000rpm higher then normal?
Oh yeah my fuel relay is out by the WOT cutout for a/c.
Your computer harness should have one brown plug on it and the dash harness should have one brown plug on it as well. 90 and earlier had a gray and black pair in the same spot. They rerouted a bunch of circuits in 91, then even more in 92.5. So there are 5 harness configurations. 87-88, 89, 90, 91 to 92.5, and 92.5 to 93. You need the last and hardest to find it seems.
I'm definitely gonna copy this info into my phones notepad.Good info to know.
---------- Post added at 10:20 PM ---------- Previous post was at 10:06 PM ----------
If I trouble shoot a harness or component under the hood,Im good to go but once you get me near the dash area,I get scared as hell.lol.Its good to know all 3 of your issues are caused by a simple harness change.Well its simple for anybody but me,that is.lol.Good luck on the project Calypso
Really good chance since you have a bunch of stuff not working correctly. As I previously mentioned, a bunch of circuits were rerouted with the change in harnesses/years. I would get a 93 dash harness and swap it out, then done.
I've never pulled my dash either,so I know what you mean.I've changed my heater core before,but never pulled the entire dash.It would be kinda cool & a learning experience too,to visually see what all of the under dash components look like.
If I have to do my heater core again or replace something else,I'm definitely gonna discharge the r-134 & replace the evaporater core too,while I'm in there.
From what I've read,the main thing you have to be sure not to do is use an auto o2 harness if you've got the dual clutch pedal switch that came factory equipped in the 5 speed cars.You can use a manual or auto ecm with either transmission,but if you've got that clutch pedal switch, you have to make sure you don't use the auto o2 harness.That's what I got from everything I've read.That's how the EEC-IV guru Joel 5.0 at sbftech put it anyways & I trust his judgment.
Let me ask you this since you're up to date on the harnesses.Is the harness identical between the auto & 5 speed,meaning do both cars have the wiring that's used to connect the clutch pedal switch?? I guess if the answer is yes,it wouldn't affect the ecm anyways unless the harness was actually plugged into a clutch pedal switch. In otherwords,if you've got a Mustang that came with an auto transmission from the factory and the wiring is in place for the use of a clutch pedal switch,but a switch isn't there to be plugged in,the signal return line won't get blasted with 12 volts anyways because the switch is not there to provide the 12 volts,right??Hope my wording is not confusing.lol.I confuse myself sometimes.The problem occurs when you push the clutch pedal down then crank the engine,so if a clutch pedal & the switch isn't there to begin with,the problem shouldn't occur.
(To make it simple & easy to understand,it was worded like so)
*Auto O2 harness* =neutral safety switch and presence of 12 vdc during engine cranking
*Manual O2 harness*
= SIGRTN sourced through clutch pedal and trans gear switch no voltage present. Mix the use of an auto transmission O2 harness with the clutch pedal switch, and the ECM will burn tfromandTN line at the module everytime the clutch pedal is depressed & the engine is cranked.
Sorry I went offtrack from the thread topic,but wanted to bring the info up for reference.
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