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i now know why i have no reverse

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Old 05-13-2009, 07:55 PM
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Default i now know why i have no reverse

well i hooked up my efi live and found a pid for the pcs so i decided to check the pressure that way while im waiting for my gauge to get here. i dont know how accurate checing it this way is but it turns out i def have a pressure issue. at idle it was ZERO revved it a bit and saw 5-10 psi. so then i unhooked the tps sensor to get max pressure and it only went to 30psi at idle in gear. 45-50 psi cruising and only 90 psi at wot. i revved it a bit while in reverse and the car did move very slightly. i have no codes for the pcs so im wondering if they will even throw a code when faulty. or its gotta be my teflon rings since they were the only things that didnt get installed properly( dont have a resizer for the input shaft or an installer/resizer for the r. input drum. took it for a ride with the tps off and the car pulled alot harder leading me to believe that its also slipping in the forward gears...hard to tell with my loose 3600 stall. so whats your opinions on this? ill probably replace the pcs solenoid before i pull the trans back out and apart.
Old 05-13-2009, 08:07 PM
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That is not your line presure . Thats your AFL presure , Something different, It affects line presure by acting on the PR valve. And the PSI your seeing is not real either, The 60e has no presure sensor like that, What your actually seeing is a estimated AFL presure. The PCM looks at how much currect its send to the PCS and uses that number to estimate the AFL for what your trying to determine the information you are getting there is useless. Do not waste your time changing the PCS
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Old 05-13-2009, 08:26 PM
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ok i wont change the pcs yet. but either way its def a pressure issue since i did feel the difference after disconnecting the tps sensor. hopefully my gauge will get here soon so i can see what its really doing. i was just using that method to try and get some idea...being very mechanically inclined, when it doesnt go right i will not rest untill i figure it out and get it right the second time if not the first. im very determined in that way..
Old 05-13-2009, 08:31 PM
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I understand the determination. But even low line would likley not result in NO REVERSE slipping reverse yes but nothing at all I dont think so.
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Old 05-13-2009, 09:25 PM
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When your pressure gauge arrives, use the EFILive scantool to command the PCS to full pressure (96 psi) [see below], and the pressure gauge should show something 175-220 psi (check your service manual).

In the EFILive scantool:
- connect to vehicle,
- goto DVT tab,
- select controller (99-08 PCM),
- goto Auto Trans subtab,
- slide PCS current to 1.3A (corresponds to 0 psi Torque Signal pressure; TS is produced by PCS from AFL),
- checkmark PCS current,
- click Activate at the top,
- line pressure gauge would read 0 psi,

Then:
- slowly slide the PCS to decrease it, line pressure gauge should should increase,
- when PCS current is zero (corresponds to 96 psi TS pressure), line pressure should be 175-220 psi.

[check your service manual, or Frank would know the number for your application].

As you slide the PCS current back and forth, line pressure should vary...

Remember this:
PCS min current 0.0A == max PCS pressure 96 psi == max line pressure 175+ psi
PCS max current 1.3A == min PCS pressure 0 psi == min line pressure 0 psi

EFILive scantool displays the commanded TS pressure (the pid name is TFMPRS)...
like Frank said there is no pressure sensor.


When done, click Deactivate and uncheck PCS Current.

Last edited by joecar; 05-13-2009 at 09:30 PM.
Old 05-14-2009, 04:15 AM
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Thanks for the tip joecar, i do have the pcs pid set up(TFMPRS) and its reading o.o psi then after forcing full line by disconnecting the tps(didnt realize it was in the dvt menu) it went to 30psi under the pcs at idle.but ill make sure to take a look at it the way you said when the gauge gets here.




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