We have a question regarding a 1990 Caddy Sedan Deville with a 4.5L FWD.

We are trying to tune up this car, starting with the cap, plugs, wires. We bought a Haynes manual to help us with this, but it's the wrong one!!

We figured out the firing order by looking at the intake (1-8-4-3-6-5-7-2), but, we are unsure as to which position on the distributor cap is #1. We know this is a slightly dumb question, but with the wrong book, and not being able to find the answer on the internet, we could use the help!!


Thanks!!!

um, follow the #1 plug wire to its spot on the distributor. I believe thats what your trying to do.

It's not that easy. The person who had it before had the wires in the wrong order we believe, so think of it as we are starting from scratch, like installing new plug wires after stupidly pulling them all off at once. We figured out which cylinders are which and which wires are which, but we DO NOT know which order they go on the cap itself at all. I hope that clarifies...we just need to know which position on the cap itself is #1, so we can put the wires in the correct spots....

Uhhh, I dont' think that the car would run if the wires were incorrect. Um I really dunno what you should do. Get a haynes manual.

18436572 is the standard GM firing orde.r

It will go from top left, couterclockwise to the top right...

Thank you elwesso, that was what we needed to know. And thank you RBraczyk for trying. :) We did figure it out on our own a little while ago, by crossreferencing a book showing a 5.7L Chevy firing order and #1 on the cap diagram, and paying attention to which way the rotor moved when turning the engine by hand.

We were just hoping that the experienced Caddy guys could offer some advice to us faster than we could scratch our heads and swear. :)

We do need one more piece of advice, if anyone is able....

Are there any good internet sites that would show wiring for the heater relay? The Caddy comes to us with a "hotwired" blower motor (ie, someone cut into the wires under the hood and tapped in with a toggle switch that they ran through the driver's door and laid on the dash inside). We would prefer to fix it properly. Any advice would be great.

Thanks so much!!

Oh, i have a chevy 5.7. Didn't know it was the same order...

Sounds like you are goingto be doing more work on this car such as the blower motor wiring. you would be well advised to get a factory service manual. They are worth their weight in gold even at the new price. Not sure if you can still get an '85 from Helm but you can probably find one on ebay. Chilton and Haynes are realtively useless for all but the basic stuff.