help please! No throttle response
 

After installing a new head gasket and finally getting my 1990 n/a supra to crank I discovered I had a miss. I actually had good throttle response with the miss, but today I installed a new distributor cap, rotary button, plugs, and plug wires. I got it idling perfect with no miss, but when I gave it gas the rpms slowly climbed and topped out at 3500 rpms. Also when I turned the car off I could hear the radiator bubbling and dream was blowing from the overflow tank, so apparently the car got a little hot. Can over heating cause sluggish throttle response? Thanks for any info, I am open to any suggestions!

update on the problem
 

So I let the engine cool off and filled the radiator with water. Then I cranked it up with the radiator cap off and tried to rev the engine. Still no throttle response and water was gushing from the fill up neck on the radiator... I have never seen anything like this before! Someone please help! Thanks

thermostat

Would the thermostat cause my lack of throttle response?

Maybe and did you try calibrating the tps

I haven't tried that, but I had good throttle response last night before I put the new plugs, wires, distributor cap, and rotor button on... wouldn't that indicate the GPS was functioning properly?

That was supposed to say tps instead of GPS... LOL. Stupid smart phone! Anyway, I discovered another piece to the puzzle... After taking out my thermostat, I ran the car and it is still very sluggish. This time though, I found that my exhaust manifold was literally glowing red! Stopped up cat? If so, why would that affect my coolant flow? Is there something more serious going on here? Any input would be greatly helpful...

Glowing red hot exhaust manifold/ coolant gushing from radiator fill-up neck!!!
 

What the #@&$ am I dealing with here? I just replaced the head gasket on my 1990 n/a supra. Also new plugs, wires, distributor cap, and rotor. I have very very sluggish throttle response and I am lucky to get the car to rev to 3500 rpms, but it idles great... Any ideas? Any input would be greatly appreciated. Thanks

Sounds like maybe your ignition timing is off. I can't remember if a red hot manifold is a sign of advanced or retarded timing. But that can also explain your sluggishness.

Check timing I rebuild my motor and the distributor was off a few teeth. it run but like crap and I have a aftermarket header and two pipes was glowing red.

Thanks a lot for the info. Any ideas on my coolant issue?

Thanks a lot, that helps a ton...

Merged your 2 threads on the same topic

a glowing manifold is waaaaay advanced, ur running super lean basically. actually your fuel just isnt burning all the way, then its flowing into the manifold and being burnt there. do some tuning, check your dizzy. ur prolly reaching full advance at 2000 rpms or so, getting crappy burn rate readings from the 02 sensor, not to mention conflicting signals from the other sensors, and ur computer cant compensate the timing accordingly. get that right or say bye bye to your exhaust valves.

this would also explain the over heating, as u are essentially flash boiling your coolant, and possibly creating more air pockets in the passages. get a new thermostat, check you timing, make sure its dead on (retard a few * if anything) then purge your coolant system.

hit back with results.

red hot exhaust
 

Hi!
A glowing exhaust manifold clearly indicates that your ignition setting is RETARDED and needs to be advanced a few degrees.an old tip for setting the ignition was to set the throttle to a fast idle and turn the distributer either way until the revs peaked --this was the best way of finding a starting point to reset the timing , if it " pings "( sounds like coffee beans dropped on a empty biscuit tin = pre-ignition ) under heavy/hard acceleration then it's too far advanced and needs to be retarded (backed off ) a little .I know from experience -- a guy had a van that had the same red hot exhaust problem. this was fitted with opening and closing points system ( very-pre electronic system ( 1970's ) and the points had closed to 0.005 thou. -should have been 0.015 thou. which meant that the spark was late( RETARDED) and therefore the fuel was still being burnt as it was being pushed into the exhaust system ,making the exhaust manifold red, I opened the points (advancing the spark to correct setting )and cured the problem.

^^^my bad. *hangs head in shame...

totally thinking backwards there, thats what i get for staying up late with a beer in my hand, then trying to post...FAIL.

Also, be sure to check the ignition timing per the TSRM. This means vehicle is at operating temperature, you have no diagnostic codes, and the jumper is in the diagnostic box. Failure to meet all these requirements will almost guarantee a false reading of the ignition timing.