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missing/hesitations while cruising and 3800 hesitation (logs)
Im having problems with my 88 TII: Rtek 2.0, 720 sec's, full intake/exhaust, FMIC, no rats nest. I know there are a million threads on hesitation probs, but ive searched and searched, and Im still stumped and need some help.
Ok lately after a 200 mile trip i noticed at cruise, i can feel slight missing/hesitating around 2500 to 4000 rpm. When accelerating, i can feel it missing when i go through that rpm range. I logged it while it happens, and i couldnt see anything out of the ordinary; the secondary flag stays off, so that means its not the 3800 hesitation, right? TPS is steady; boost is steady vacuum around -10mmHg. I dont have a log saved yet, i will make one tomorrow on teh way back from work.
A related problem that ive had ever since i bought the car a year ago is bad hesitation when accelerating with part throttle, between -10mmHg and 3 or so psi around the staging point. No hesitation when accelerating at WOT. Attached is the log of a WOT run in 1st. No hesitaiton when accelerating slowly, only hesitates at low vacuum or low boost. If the secondaries turn on fine under WOT, it means its not a grounding problem, right?
Things ive tried:
new spark plugs
new fuel filter
grounded ECU GND pins
cleaned injector ground (under uim)
relocated battery (fmic install) and cleaned battery ground
reset TPS: works normal, smooth transition from 20 % at idle to about 88% at WOT
there is no restictor pill in the boost sensor line, I want to try that, but i have no idea where to find one? Right now i have a capped T fitting in the line, thinking it will do the same thing. But do the boost logs look fine to me, they dont look spikey?
any ideas?
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As well, I would replace the injector clips. I went though hell with that hesitation. Did all the grounding as explained in the FAQ, including replacing all the clamps or eye clips. Still the main problem. Then, Karack recmended checking my injector clips. I could not see anything, but decided to replace them anyhow. BAM! That took care of it. The grounding I did prior did get the little hicups out, but not that terrible stumble right around 3650. Really worth changing them. If you changed you injectors, chances are it could be the clips. Bosch clips work fine. Look in the 2nd gen section for a writeup by Karack.
about the injector clips, wouldnt that make it hesitate all/most of the time at the staging point? Why does it run fine at WOT? It never hesitates at WOT, which makes me think its a sensor or something. I made some cruising logs this mornign, ill post them tonight
9_26_06-cruising2.pdb
just keeping speed steady at 45 mph or so, small hesitations
9_26_06-accel1.pdb
accleration at near 0 psi, semi-violent hesitation in 1st gear, none in 2nd
9_26_06-accel2.pdb
acceleration at near 0 psi, same hesitation but in 2nd gear, none in 1st
Then i pulled over and unplugged the TPS out of curiosity.. Did about 3 runs without any hesitation at all!! I thought i figured it out! but then on the 4th run, it hesitated again. But unplugging the TPS definately helped a lot! it didnt hesitate nearly as much
9_26_06-tps.pdb
TPS full range movement, it looks good to me??
Did you remove your block at one time? I went through three installs in the last three years. Bought a blown J-spec, then a Atkins rebuild that had a bad oil pump. Then a Kevin Landers rebuild which has been great. What I am getting at, it is then I started to experience small hessitations. Removing the harness caused this. So, I cut off all Eye loops ect, and replaced them. Regrounded all conenctions. Adding new Eye Loops also allowed me to clean the wire back before putting the new connectors on. That took care of all my small hessitation. However, giong under low boost kicked like a bitch. I chased it for a month then changed my injector clip and walla. All good. It is really worth changing all the connectors for new. Adding extra grounds was a waist of time in the end. I just needed fresh connections.
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