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02 NFA. 1900 rpm on WOT in park. No codes.

Dron

Full Member
Joined
Oct 12, 2005
Messages
83
Location
NYC
I replaced the 5.3 (old had bad injector and hydro lacked), replaced 4l60 (it was antifreeze in the ATF). 4l60 was rebulbed by "one man shop" (newer used this guy before and no reference, just take a chance).
Relearned crankshaft position sensor (CKP). I drove around, and tyranny doesn't downshift right. I parked AV, reset PCM and now no reverse. 1900rpm on WAT in park. When I switched to "N"- rpm higher on WAT). No codes, no misfire. On WAT in neutral- ATF is dripping from went hose.
Tranny solenoids are switching properly (1-st Gear: 1-2 =ON, 2-3=ON and so on). I se hesitation on PNRD321 indicator- switching from R to P. Handle in park, indicator "R" stays on, release the breaks- "R" goes off. I aske local mechanic for serves- hi is overbooks for next 2 month.
My next steps: 1) replace TPS (I can see TPS is working on the scanner). 2) will check tranny shift/park switch (I have extra one).
Should I bay remanufactured tranny (with dyno tested) and tow the track to bigger shop for repair. Or continue education to practicing DIY on my truck?
 
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what is WAT?
 
I can work on AV on weekends only, it is parked 2 hours drive from my home.
I'll check TCC on the tranny next weekend. There new (or rebuild) converter. Cooler and lines was flashed.
 
I have read post 3 times and I am still unsure what your issue is other then tranny does not work - I think?

Can you explain in more detail your issue?
 
1) I replaced blown engine. New sparkplugs, sparkplug wires. Ignition coils are good. Check engine light start flashing pass 2000 rpm. Code P0300. I check vacuum-good, fuel pressure-58psi. Relearn crankshaft position sensor- no more cods.
2) I had no problem with transition before old ending hydro locked. I pumped ATF throw deep steak tube. ATF was pink. I replaced radiator, replaced transmission.
3) I take AV for a drive test. No problem upshifting. AV had hesitation on downshift.
4) I contact transmission mechanic with this issue. Mechanic tell me to reset Transmission adaptive pressure (TAP) information.
5) I park the AV, Connected chip scanner. I check with scanner all solenoids- they are switching correctly and no open or short wires.
6) I clear TAP.
7) I start the engine and found out that there no revers. I went throw the gears, AV is moving forward (I have couple feet space to move forward).
I rev the engine to WOT on park. Engine rev to 1900 rpm, than cut off acceleration (not stole) and it stays on this rpm does not go higher. It is feel like driving on highway wen you reach engine cutoff speed, engine loosing power.
9) I put shifter to N and engine can rev to higher rpm. I noticed, ATF start drippings throw vent tube when I do that.
Engine idling perfect -no check engine light, no cods.

What I planning to do:
1) replace TPS (I can see TPS is working on the scanner). 2) will check tranny shift/park switch (I have extra one).
If this wont help:
1) I'll install original file to PCM. Or maybe I will flash PCM first, then everything else.
 
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Might be a stupid question but did you do a throttle body relearn??
 
Thank you Randy,
This year I get a lot of mechanical education and practice: Remove engine and transition from donor track. Remove blown engine from my AV and replaced with donor engine. Remove transmission from my AV and install donors tranny. Then removed transmission from another donor, rebuild (by other guy) and swiped with tranny on my AV. I feel like I'm working for AMMCO. I paid my mechanic to replace 5.3l over $3K 2 years ago. So, I saving money and getting knowledge and the time is my payments for it.
Ok, back to topic:
No, I relearn only crankshaft position sensor, before replacing transition. I drove about 15-20 miles on old transition and that time relearned CKP.
I don't think about throttle body relearn. 2002 AV has cable throttle body and there TPS and IAC sensors. I drove the AV for 20-30 miles and engine was acting normally. Maybe, I should relearn everything, after resetting PCM? Relearn TPS, CKP and what else?
I can't relearn CKP before a issue with 1900 RPM will fixt.
I will check my i400 scanner if it has option to program throttle body.
Thank you.
 
Mine is DBW built in September 2001.. You must have a real early AV if it has a cable TB so I don't know if it has to have the relearn procedure performed. Basically with the DBW TB if it's replaced, disconnected or if you clean a lot of carbon off it you change the airflow characteristics thus the idle, so you may need to do a relearn. On DBW it's as simple as starting the vehicle letting it idle for 3 minutes, shut it off for 1 minute then start it again and idle it for 3 minutes and it should do the learn the new throttle position and idle at the correct RPM.

But with cable TB I'm not sure. The cable should have an adjustment screw or something to set the idle if the ECM doesn't have control. So this probably not your problem..

It's the throttle position, map and MAF sensors that will be affecting the idle and RPM. I would drive and look at load, see if if it loads goes up past 90 percent at WOT, if not it could be the MAF..


Good luck
 
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