92 hatch, d15b7, 170k miles
aftermarket i/h/e, new dizzy, wires, map sensor, thermostat, running p06 ecu

so my d15b7 was running rich for a while. after much searching i found that the thermostat was missing completely(from previous owner). i also had a bad bucking problem at low throttle. bucks violently in any gear under 2-3k rpm. i did notice a lil oil on the plug threads. recently replaced the top and bottom orings. now for the questions...

1. i reset the timing while the thermo was missing. now that i installed the thermo, do i need to re-time?

checked motor mounts(and even re-installed the ac bracket and torque mount). i am running the burnt plugs from before the thermo. i DID clean and sand paper them. i didnt want to put my new plugs in until i determined it was no longer rich.

2. that being said, could the fact i timed it while it was running open loop cause it to buck still? i am at a loss trying to stop the jerking/bucking. idles around 1k, seems steady enough.

and as always, any help or guidance is greatly appreciated.

 

bump

*update*

after a week of driving my spark plugs havent been fouled, so i put the new set in last night. still getting the bucking.

 

Change fuel filter, distributor cap and rotor and wires, might want to check your air filter too.

 

Sorry, should have mentioned...
Brand new dizzy, wires and my short ram is about a month old and is still clean. I'll try the fuel filter.

I actually drove it about 45min on the hwy yesterday(avg of 60 mph). It overheated at the first light I came to. Me thinks it had a blown hg and the po removed the tstat to sell me a car that doesn't overheat. Couldn't see any visible leaks and both upper and lower hoses were scorching hot and very bloated. i managed to get them temp down by turning on the fan(was sitting at a red light). then with the fan running, i tried to take off on green and i got a cel and the rpm's started surging. being in traffic, i turned off the fan, then the car completely and restarted. cel and surging was gone after restart.

Could a blown hg cause the bucking? Do I need to reset the timing and ecu?

 

please advise, not ready to swap the b in yet. my dd truck(v8) is killing me on gas and id like to drive the hatch...

 

I'm going to suspect timing. Both mechanical and ignition. You never said if you did one or the other or both. The overheating could be a sign of a headgasket problem. You can perform a pressure test, compression and/or leakdown test to verify. Do not run without a thermostat OR with it overheating.

 

we did ignition timing only. mech timing is the checking of the cams to crank position?? sadly i ran it quite often before i found the missing tstat... ran super rich