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Well, I got to drive the old beater truck today.
What a slow piece of crap. :cry: I have only 1 code and its a p1258. Something about the shift soilnod-A. I don't now what's wrong but the damn thing will barely pull its self down the road. The motor is revving very slow and sad. :cry:
IM still wondering about the inj. I had to put in to make it run. :duh:
Does anyone now what size the 99 5.3L INJ. where and what size the 05 5.3L INJ. are?
Are you getting a good 1-2-3-4 shift?
Yes!
It feels like its in limp home (or mode). Just no power at all.
Thats why I was asking about the inj. Maybe there bigger or smaller than what I had it tuned for.
How much fuel pressure do you have at the rail?
56psi. and drops to 48 when I rev on it.
The 99 5.3L is a 19# and the 05 is higher i know, 24# maybe? the 99's had smaller cam, injectors and diff pcm.
Chris
You have a fuel supply problem of sorts. You should not be dipping when you rev the engine. Your PSI should remain consistant. Low fuel pressure will cause drivability problems. I'd start there. Under a load while driving you're probably dipping a lot lower than that.
I just drove it in the shop and it spun the "tire". Of course it was wet outside.
We will get it figured out Dustin. :thumb:
The 99's had 19lber, the '05 had 24lb or 38lb'ers, depending if it was a flex fuel truck.
I doubt you have the flex fuel injectors, it would be fouled out by now and smoking black very badly, no power at all, but with lots of sputtering and smoke.
If you have the 24lb injectors in there and I tuned for 19lb'ers, then it'll still drive and drive just fine at wot, it may be a bit rich, but still run.
-What do the ltrims look like?
If the are 25+ or 25-, then something is up. Maybe bad 02's, what 02's did you use for the truck?
-I'd get the fuel pressure checked under a load
-You shouldn't have any trans codes popping up. Is the truck starting out in second?
-What about all those wires that were unidentified? Did you get those figured out?
Keep us updated, we'll get it,
allen
(-What do the ltrims look like?
If the are 25+ or 25-, then something is up. )
How do I check the I trims.
Maybe bad 02's, what 02's did you use for the truck?2002 LS1 O2's . They wouldn't set a check light if they where bad?
-You shouldn't have any trans codes popping up. Is the truck starting out in second?I don't think so.
-What about all those wires that were unidentified? Did you get those figured out?
Yes.
When I drove it to the exh. shop it ran fine (no power) for about 4mls then it started sounding like it was running on 4 cyl. I could barly get it on the lift at the shop. After they finished the exh. it ran fine untill I stoped to get gas. After getting gas (93) it ran the same way sounding like it was on 4cyl. When I got back to my shop I killed it and restarted. It ran fine agin. I drove it around the parking lot a few times today and it ran fine just no power.
I have cats and it does smell rich, but no smoke at all.
The inj. came out of a 05 Yukon 5.3L.
Thank you Allen for the help.
Do you have all your grounds grounded properly? I had a loose one and I think it was making mine run like a 4 cylinder when it wasn't working properly. I found the loose one when removing the dead engine. Your harness was a stock unit modified by someone to run in your truck?
Still I think your fuel supply is suspect at this time. You need to monitor the fuel pressure while driving or on a rolling road dyno.
You'll need to get a scanner, one that reads live data. The ltrims should be moving a bit, as well as strims. The 02's can be the wrong ones and not throw a code , yet. Get a scanner and see if they are toggling up and down, from about 50mv to 900mv. If they are sitting around 450mv, they are bad or the wrong ones. If they are at ZERO then the wiring is wrong.
Do you have your gas tank vented?
keep it coming,
allen
I used the factory vent on the tank. I just hooked up a rubber hose and raped it around in a circle a few times.
If the pressure is low can I try turning up the regulator.
Where should the vac line becoming from for the regulator. I broke off that tab on the pass. side of the intake and ran it from there.
You should not have a vacuum signal going to the regulator. It should stay at a constant 58 lbs of fuel pressure at all times. The vacuum signal would typically boost the fuel pressure during low vacuum signals on older engines. GM programs the PCM compensating for a steady fuel pressure rate. I guess Allen would program it differently if you had a turbo on the truck and were not running an FMIC.
You can adjust the regulator, at idle, get it about 55-58psi. It should stay above 52psi during a hard run or lots of load.
The vaccum line is fine where you put it.
allen
Thank you again Allen.
I have some things to check now. Ill let you know what I find tomorrow.
I put one of your NELSON PERFORMANCE decals on my truck. I think Billy's going to get me a TRT PERFORMANCE decal that is just a little bigger to put right next to it :laugh: :laugh: :laugh:
No problem, just keep at it, you'll get it.
Thanks for sporting the sticker,
allen
P1258 is Engine Coolant Over Temperature (Protection Mode Active) The pcm will disable a number of injectors when the pcm thinks its over temp. What was the last thing you did before it through the code?Quote:
Originally posted by BEATERTRUCK@Dec 13 2005, 06:52 PM
I have only 1 code and its a p1258. Something about the shift soilnod-A.
P1258 - Engine Coolant Overtemperature - above 268°F - Protection Mode Active
Damn, I researched it and found the same thing. :whack:
Maybe you have a short in the coolant temp wiring or have it wired incorrectly. Did you do a two wire or three wire coolant sensor?
I made my post from the front page as the code/description stood out incorectly.
I see now that you have a little project on your hands.
What you describe and the code given match. The PCM will alternately disable 4 injectors untill corrected. Make sure your wired corectly
C1 (BLUE)
Pin 74 (ECT Signal Wire)
Pin 63 (ETC Sensor Ground)
Make sure there correct not grounding out etc..
If that checks out its the puter its pretty cut and dry.
BTW is there any messages in the IPC other than SES? What is your gauge reading?
My bad! I had that code when I first started the truck. The only code I get now is a P0753 I think. Its not right in frount of me. I can clear the tranny code and restart the truck, but as soon as I drive it the SES light comes back on . The tranny code is the only code I keep getting.
Sorry about the mix up.
Well that sucks P0753 can be a real bitch to diag. Either Open, short to ground or Short to power in the 1-2 SS Circuit. If your lucky Ignition Fuse 0 is open I would check that first. I dont have with me now but do have the Flow charts and schematics for this.
Hmmm....this might explain something, the atsg manual says that when you have the engine coolant over temp error the tcc solenoid will be applied. Having the convertor locked at all drive times would definitely kill your performance. I guess if that was an old error code and not the current one it doesnt matter.
FWIW solenoid A is the 1-2 shift solenoid.
I believe the pcm will command 2nd gear or 3rd gear. That would explain the low power but what doesnt make sense is why it SOUNDS like a 4 cylnder sometimes.
Remeber to check the Ignition 0 fuse. It is the main power source for the 1-2 SS (pink wire)
? With the swap you hook a wire to the brake switch to disengage the convertor when the pedal is pushed. What effect would this have when you stall the truck up or when you power brake?
Does any one have the wiring for the tranny plugs?
Yeah, that is a purple wire behind the glove box in that white/clear plastic connector. It is to drop the power to the TCC. It has 12v until you press the brake pedal and then it has 0v. The plug wiring diagram is in an ATSG book if someone has one handy otherwise I can get it for you tonight.