I'm planning on buying a 87 Supra n/a, 5 speed. For some reason it missfires at idle but drives fine. I was told by some mechanics that a missfire at idle that goes away with some rpms is a burnt valve or it is running lean. I don't think it's running lean.... doesn't seem to be fuel starved when you get on it. Are there some other things that it could be? The guys says he replaced the plugs and wires. He also said you have to take the intake manifold off to do it... that's gay. Let me know what ya'll think.

Well dude. It's probably going to get worse before it gets better.
And if your attitude at this point is "gay". You may be better off with something else.

I say this only because these..., are hands on cars.
If you aren't mechanically enclined.

If you take your roller to a shop.
You best have deep pockets so far as any, supra is concerned.

Edit: It sounds like the timing could be lagging just a hair.
Make sure everything is at tdc and check the timing.

"that's gay" is just an expression. I can do it... it just sucks. I was planning on checking the timing but to be honest I just plain 'ol forgot about it, LOL. I just finished replacing the front pads and rotors yesterday. I am gonna have to find a place to buy the original Toyota Supra repair manual. I was gonna take the hubs off to get the bearings replaced and couldn't figure it out. To be honest I didn't try too hard cause I really don't know what I am doing when it comes to hubs but I am gonna have to learn cause these front bearings are shot!

I've got a timing light so I can check the timing tomorrow. Supramacist did you mean the timing should be set to 0 or TDC at idle? Sorry if that is a dumb question. Just wanna be sure.

Thanks:thumbsup:

tdc is when your #1 cylinder is at Top Dead Center on a compression stroke which means both valves are closed. that is when all timing marks should line up.

Check down by your crank shaft.
Clean it off real well and you will find a gauge.
I think 0 5 10 15.
0 being top dead center.

Do this before playing with the timing at all.
On the ge you can adjust the timing over by the dist cap.
I can't say anything on the gte engine, for I have 1 not.

I am about to go check the timing right now. I was wandering what the timing should be at idle though. Is it supposed to be at TDC at idle or a few degrees ahead? And you said the adjustment for this is right beside the distributor.... on most cars it is the distributor. Don't you have to loosen the distributor hold down bolt and turn the distributor to either advance or retard the timing? Or are Supras different?

Okay so I was about to check the timing and once I started looking at the crank pully, I'm noticing multiple indentions in the pully that all could resemble TDC.... is it supposed to be an indention on the rear of the pully(crank side) or front of the pully(radiator side)? I know normally you go off of an indention on the rear of the pully but I have also had a car that you went off the front of the pully so now I'm stumped. I've got a small indention on the rear of the pully, a notch(could just be a defect) on the front of the pully, and a small circle with a dot in the middle of it on the front of the pullly. What do you guys think?

I'm also seeing some other problem areas under the hood. I've got quite a bit of stuff that is just not connected or plugged into anything. There is a cavuum line connected to some kind of a vacuum diaphram beside the throttle body with some kind of a filter attached to it that is just not attached to anything. Then I've also got a vacuum line on the bottom of my air intake tube that isn't connected to anything. I plugged that one cause I couldn't find anywhere for it. I also have a lot electrical sensors that aren't plugged in. Most of which don't seem important except the knock sensor connector which I did plug back in but it didn't change anything. So I'm stumped as to what direction to go from here.

There is a vaccum line diagram on the under side of your hood if you have the stock hood.

Any idea on the timing? Which one of those marks do you think is probably TDC?

The zero or the 1st one.

Your timing can very by 5 to 10 degrees either way and still be good.
You just want to start from tdc so you know where to go back to while seeking the sweet spot.

Well I guess I'll just try calling the Toyota dealership and asking someone. I hate to mark the one I "think" it is and adjust the timing by it and then get it all out of wack. I'm sure someone in their service department will be able to tell me.

Order yourself a tsrm while you're at it.
It'll keep us from bumping heads when you start reading pretty much what I post.

If you set it at the first mark you are there. It's zero.
You can't really mess this up unless your cam gears are out.

If you're going to replace your idle tensioner pulley.
You may want to replace that spring as well. Don't drop it in.
Because you'll have to pull the entire plate off. to get it out.

I had to pull the crank shaft pulley off to access the timing cavern.
I'm sure you'll have to as well. It's old and brittle. Don't brake it.
You're going to need a half inch drive breaker bar and a cheater bar to bust that thing lose. I believe it's a 19mm socket.

Unless you have an air wrench, and I didn't at the time.