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Performance, Brainstorming & Tuning Talk about modifications, or anything else associated with performance enhancements. Have a new idea for performance/reliability? Post it here. No idea is stupid! (please use Detailing and Appearance for cosmetic ideas)

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Old 12-03-2004, 07:16 PM   #81
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Additionally I have to wonder what differences there would be from Ser. I to Ser. II. Any ideas?
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Old 12-03-2004, 08:40 PM   #82
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It'* in LT block 0 at idle and 9 at WOT.

The 02 reads normal at idle and part throttle but over about 55% TPS it goes progressivly leaner until 15-20mV at WOT.

What all controls injector pulse width?

Also, Sometimes the car wouldn't start and would let me crank for 10sec or so, very annoying, only did it if it sat for over 12 or so hours. Earlier today I hooked up my FP guage and started the car. It cranked and cranked but as soon as FP came it started right up. WTH makes the pump not give me pressure? Is this strike two against the pump?
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Old 12-03-2004, 11:35 PM   #83
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Bad wiring to the pump?
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Old 12-04-2004, 12:01 AM   #84
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FSM 6E3-B-3 (Lack of power, sluggish or spongy)

things it says I should do. Things I did

Preliminary checks:
Visual check of everything Everything looks good
Compare to similar unit to make sure there is really a problem Yup, Trav has power clean across the band.
Check air filter I cleaned it not two weeks ago

Fuel System:
Restricted fuel filter Filter six months old
Fuel pressure Book calls for 41-47psi. I have 38, but so does Trav.
Contaminated Fuel Doubtful through 3+ tanks

Ignition System:
Check secondary voltage How would I test this?
Knock sensor for false knock I'm not getting knock when running and none get I flip to WOT, rockers must have been causing my false knock

Additional Checks:
PCM Grounds I've cleaned both.
Alternator output voltage Good.
Exhaust system for restriction Had bad cat, Replaced it. Runs better but still not perfect
Shift solenoid sys and TCC for proper operation The scantool shows me what gear it'* in and it shifts right
For DTC 68 No Codes.

Engine Mechanical:
Engine valve timing and compression 165-167psi on all cylinders, I assume the timing chain is original
Check for incorrect or worn camshaft How? pull the valve covers and measure lift?
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Old 12-04-2004, 12:54 AM   #85
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Quote:
Check for incorrect or worn camshaft How? pull the valve covers and measure lift?
Yes, that is exactly how you check your cam. You will need a dial indicator.
Also check the valve stem height.
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Old 12-04-2004, 01:07 AM   #86
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Quote:
Originally Posted by DrJay
How did you compare the two to determine your fuel delivery was fine? I'd keep my left eye on it still. Have you replaced your o2? It might be ready for it if not. The PCM won't do any trim adjustments at WOT because it actually ignores the o2 sensor. It does math from the adjustments it makes at part-throttle/cruise and such. Like it figures if at 50% throttle it needs an 8ms injector pulse, at 100% it'll make it 17-18ms to be on the safe side. So try resetting your pcm and giving it 20min or so of part-throttle city cruising to relearn, see if that changes your o2 at WOT.

What are your idle o2 readings? Cruise readings?
I had 38psi at idle, He'* got 38psi at idle. I put my brand spanking new FPR on his, still 38psi at idle.

02 is ~4 months old

idle 02'* are really bouncy in the 500-900 range. Same when cruising but go lean when I touch the gas.


Quote:
Originally Posted by 2000SilverBullet
Yes, that is exactly how you check your cam. You will need a dial indicator.
Also check the valve stem height.
M'Kay, Now just to find a dial caliper.
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Old 12-04-2004, 08:06 PM   #87
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Super Duper findings today:

I've 14.5V at the alt, 14.3V at the battery and 14.2V at the main fuse block. Power seems normal.


I finally got around to putting the dual trace o-scope on the crank and cam sensors.

The crank signal and the cam signal aren't sync'd, We got them both on the scope, sync'd to the cam signal, and the crank bounces all around. The firing point is nowhere near sync'd. Everything I've read says every six hit on the crank should sync with the cam. What would cause that? They're mechanically connected why would they change in relation? The only thing I can think of is a worn chain, and at 180K it'* not exactly a suprise. The deviation I'm seeing is about equal to... *does math in head*... 30*? God I hope not.... The deviation is exactly timed with the rough idle, everytime the cam moves forward the car stumbles. When you touch the gas the cam goes waay back, almost .5ms, then when you let off it moves forward almost .75ms.... Since I have the crank signal showing at 1ms in duration... that'* like 1.25ms total deviation or 45*.... God, someone tell me I'm wrong.... An engine with a chain in that condition wouldn't run right?
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Old 12-04-2004, 10:10 PM   #88
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Quote:
Originally Posted by Damemorder
Super Duper findings today:

I've 14.5V at the alt, 14.3V at the battery and 14.2V at the main fuse block. Power seems normal.


I finally got around to putting the dual trace o-scope on the crank and cam sensors.

The crank signal and the cam signal aren't sync'd, We got them both on the scope, sync'd to the cam signal, and the crank bounces all around. The firing point is nowhere near sync'd. Everything I've read says every six hit on the crank should sync with the cam. What would cause that? They're mechanically connected why would they change in relation? The only thing I can think of is a worn chain, and at 180K it'* not exactly a suprise. The deviation I'm seeing is about equal to... *does math in head*... 30*? God I hope not.... The deviation is exactly timed with the rough idle, everytime the cam moves forward the car stumbles. When you touch the gas the cam goes waay back, almost .5ms, then when you let off it moves forward almost .75ms.... Since I have the crank signal showing at 1ms in duration... that'* like 1.25ms total deviation or 45*.... God, someone tell me I'm wrong.... An engine with a chain in that condition wouldn't run right?
Yeah the every 6th hit syncing is cause the cam turns at half the crank speed. I've got a strange idea...If there'* a period of 10-15secs that it doesn't stumble, disconnect the cam sensor. The cam sensor is really just for injector pulsing, it'll just go off its last known good timing if its disconnected. See if that fixes your stumble
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Old 12-04-2004, 10:20 PM   #89
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Quote:
Originally Posted by DrJay
Quote:
Originally Posted by Damemorder
Super Duper findings today:

I've 14.5V at the alt, 14.3V at the battery and 14.2V at the main fuse block. Power seems normal.


I finally got around to putting the dual trace o-scope on the crank and cam sensors.

The crank signal and the cam signal aren't sync'd, We got them both on the scope, sync'd to the cam signal, and the crank bounces all around. The firing point is nowhere near sync'd. Everything I've read says every six hit on the crank should sync with the cam. What would cause that? They're mechanically connected why would they change in relation? The only thing I can think of is a worn chain, and at 180K it'* not exactly a suprise. The deviation I'm seeing is about equal to... *does math in head*... 30*? God I hope not.... The deviation is exactly timed with the rough idle, everytime the cam moves forward the car stumbles. When you touch the gas the cam goes waay back, almost .5ms, then when you let off it moves forward almost .75ms.... Since I have the crank signal showing at 1ms in duration... that'* like 1.25ms total deviation or 45*.... God, someone tell me I'm wrong.... An engine with a chain in that condition wouldn't run right?
Yeah the every 6th hit syncing is cause the cam turns at half the crank speed. I've got a strange idea...If there'* a period of 10-15secs that it doesn't stumble, disconnect the cam sensor. The cam sensor is really just for injector pulsing, it'll just go off its last known good timing if its disconnected. See if that fixes your stumble
Nope, stumble is still there, with an added DTC 41.
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Old 12-04-2004, 10:24 PM   #90
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Well the code was to be expected but still having an random studder is odd...hmm...must..think..
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