JDMFantasy2K

is the ECU good?

Zeniceguycrx

check tps voltage out put at slight throtle bad gas/air if only slight wont through a code

Donald125

make sure Ig timing and cam timing are correct. using new plugs? new fuel filter?
You said the hesitation was there before the swap. Did you reuse any part from the old motor if so what are they.

levan634

reused dizzy, alternator, starter, intake manifold (itr), crower cams, crank pulley. like i said in my first couple posts the plugs are new. i did change the fuel filter like 10000kms ago.
full throttle i have no problems. but when i get off throttle then suddenly get on the gas it hesitates and gets jerky.

when im full throttle through the gears its perfect. ran 15.6 @ 86mph in calgary alberta, Canada. im just afraid after i go boost its gonna be worse.

*the idle problem only showed up after we cracked the head from the block to put arp headstuds and head gasket. so im pretty sure that has to do with timing. i have to check it again.* unless its something worse.

what else?

JDMFantasy2K

check the o2 sensors, i know it would probably throw a code, but when i had a bad one it would get jerky.

RotaryGeek

yeah my o2 sensor went out, and it was really bad for about two hours before it finally went all the way out. it didn't throw a code till it was dead. it ran like ---- and would bog until i ran WOT. at WOT it ran really good though. it idled a little funny and would die on the road unless it was full throttle. so def check that, just buy a new one.

levan634

if it was the o2 shouldnt it have already ---- the bed since i have been having this hesitation problem for almost a year now

90dx

Run some fuel injection cleaner through it and reset timing.I cant think of alot more.Hmm.Good to see another Canuck on here though.

levan634

k i will try these things.....thanks everyone......

hatchbox90

my best bet would be the 02 sensor. this ---- was going on with my car for about 4 months, felt like ---- when cruising on the highway. i would be cruising and all of a sudden my car would kinda hesitate and i would press the gas to the flooor and 5 seconds later it would jump from realizing it was at WOT.

my other geuss would be the tps. my car kinda jerks somtimes as if im in the high rpms and completly let of the throttle. but im usually at part throttle when this haoppen . and every once ina while ill get the good ol 7 flashes from the check engine


you say your not throwing codes, but does your cluster even have a check engline bulb in there i would double check