my car has a crazy bucking problem in 2nd and 3rd gear it goes away when i floor it or let off but if i try to maintain speed it is horrible iv tried everything i could think of any suggetions?

 

my car is a 1988 se n/a if anyone needs to know

 

maybe clogged injectors? have you tried replacing the fuel injectors? could also be the fuel filter clogged....

 

TPS is probably going bad, do a sweep test and see if it is in spec.

 

noob here could u tell me what a sweep test is

 

hook an ohmmeter to your TPS green wire and the other to ground, slowly open the throttle while reading the meter and it should read 1k ohms fully closed and sweep smoothly up to the mid 4k ohm range at about 1/3 throttle. the main thing to look for is that there is no spikes in the ohm readings and that it is in spec at the top and bottom ranges.

 

8 and earlier models had a tsb go out about adding a ground to the passenger strut tower from the ground on the boost sensor.

That helped me out quite a bit but it didn't go away completely.

 

Mine did exactly what yours does until the engine was completely warmed up, then it would quit. When i switched to 93 octane it quit, so i thought i was just supposed to be running high octane since i was a n00b at the time.

 

+1 for the tps...

 

also check timing

 

do you have to turn the car on or do you need to turn the key too the second turn...i have a turbo model so id have to remove the TMIC

 

you can either do it by voltage or by ohms, voltage would be with the key on but engine off and ohms would be with the key all the way off. both testing methods should come up with the same results but voltage does seem to be a little more accurate since the resistor in the TPS can be more sensitive to faults with voltage passing through it than without.

basically just hook up the ohmmeter the same way as i listed above but set it to read volts and do the test the same way with the key on but engine off and swap 1volt for 1k ohms, at idle it should be at 1 volt and at 30% throttle it should read about 4.5 volts.

 

You can also check for 1volt at the ECU.

 

I had the same problem with my car when I first bought it- a very violent bucking. It wasn't fixed until I had the engine and fuel injectors rebuilt. That said, my car had a ton of other problems beyond poor compression, too.

 

check the CAS as well.