Well i have started to notice my car is bucking or starts to bog down every once and a while while crusing down the highway or anytime around 2500-2800 rpm. It is fine any rpm after that but when you hit the gas while it is doing this the car jerks real hard then takes off like it is loading up. Also have been getting around or below 200 miles per tank. Things i have tried to fix it were change the spark plugs, fuel filter, air filter, cleaned out the maf, checked the timing, o2 sensor, and cleaned the injectors less than 1500 miles ago. It is a 88 turbo 2 with decent compression and a hybrid turbo stock injectors and rb rev2 system and have been searching and the next thing i am going to try is check the grounds but do you think it could be the maf? I cleaned it out but thinking about switching it with another one i have. Also my car starts up and likes to shut off untill warmed up. Think that maybe a coolant temp sensor and could that be related to the other problems. Any help would be great. Thanks

 

TPS sensor

 

That was my second guess made sure it was set right on idle(1 ohm) but was at like 8-9 ohms all the way open think i might pick up another one. Thanks

 

my car has been bucking on accel, it tends to be exaggerated more the higher the gear I use, and also exaggerated when I'm boosting. thus, I haven't been pushing it very hard because of it. I thought it might be because my boost sensor vac line is a little long and until later today the restrictor pill was on the line before the bov, however after correcting that small issue the bucking continued. it seems to cruise, decel, and slowly accelerate well, but any relatively quick acceleration makes it buck. could this be caused instead by exhaust pulses on the turbo? I don't see how because I've been using the straight downpipe as it is for a couple weeks without problems until now...

 

I dont think it has anything to do with your exhaust because mine has just started doing this within the last month or so and i have had the rev2 on it and it ran fine. I do think it has something to do with the tps but also going to try the maf before spending more than a $100 on a new tps. Have you tried spark plugs, fuel filter, injectors, o2 sensor, ect?

 

spark plugs only have 2-3k miles on them, injectors are new within the last few thousand miles as well, fuel filter may be relatively new (it certainly looks cleaner than the rest of the engine bay), O2 sensor is brand new... and when I got the car the TPS was way out of whack anyway. Soon after getting the car I did the TPS checks and reset it, though, but I don't have an analog gauge to see if it sweeps properly.

 

I just used my volt meter and mine had a slight jump and think that is causing it. The best tps out of the 3 i found in my garage of parts others were way out of wack i was going to buy a new one but kinda forgot about it untill now. Luckly i work for a dealer who does have a mazda store and i get a deal on parts but i need to get some money going to need a new tranny soon and trying to get my 10th ae project back on track because we are painting it now.