L33 Swap won't rev past 1400 rpms
12-10-2009, 10:24 PM
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L33 Swap won't rev past 1400 rpms Ok, well I finally got my T56 back from the yard with a full rebuild and I seem to still be having issues reving past 1400 rpms. Here's what I got. I have a 97 Nissan 240sx with a 05 L33 and T56 and a LS6 cam. I'm running a 05 truck PCM and wiring harness that has been retuned with a Corvette/F-body file. Before I found out my T56 didn't have a 2nd gear I was trouble shooting my reving problem and came to the conclusion that the PCM was somehow being sent into abuse mode. After swapping PCM's to no avail I removed the PCM and mailed it back to my tuner and the tables responible for sending the PCM into abuse mode where maxed out to fix the problem.
Now I finally have the car back together, she started right up and again doesn't won't to rev past 1400 rpms. So, am I missing something. It was late out and about 15 degrees so I didn't spend anytime out there trouble shooting, but would a vacuum leak cause something like this? Also, the shell I picked up sat for a little over 4 years so I did pump out all the 4 year old gas, but there may have been some remaining at the bottom of the tank. Would that old gas mixed with about 2 gallons for new 89 octane give me issues like this?
Sorry to be so long winded, but I would really like to take this swap for a test drive some time this year.
Also, some of the only info I could find about abuse mode said that an Unplugged VSS could be the culprit. Well, can someone help me verify that my VSS is correct. On the 05 truck wiring harness the VSS is comprised of a green and a purple wire twisted together. I ran these wires to the VSS sensor on the T56. Is that correct? I haven't picked up a speedo calibration box, so the vehicle speed sensor wires that connect to the gauge cluster are not connected right now, would that cause these problems??? Thanks for any help!
Now I finally have the car back together, she started right up and again doesn't won't to rev past 1400 rpms. So, am I missing something. It was late out and about 15 degrees so I didn't spend anytime out there trouble shooting, but would a vacuum leak cause something like this? Also, the shell I picked up sat for a little over 4 years so I did pump out all the 4 year old gas, but there may have been some remaining at the bottom of the tank. Would that old gas mixed with about 2 gallons for new 89 octane give me issues like this?
Sorry to be so long winded, but I would really like to take this swap for a test drive some time this year.
Also, some of the only info I could find about abuse mode said that an Unplugged VSS could be the culprit. Well, can someone help me verify that my VSS is correct. On the 05 truck wiring harness the VSS is comprised of a green and a purple wire twisted together. I ran these wires to the VSS sensor on the T56. Is that correct? I haven't picked up a speedo calibration box, so the vehicle speed sensor wires that connect to the gauge cluster are not connected right now, would that cause these problems??? Thanks for any help!
12-11-2009, 11:55 AM
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Yeah, I'm still running the DBW. How can I test the throttle actuator? The throttle opens and closes fine when the engine is not running. As far as the TAC wiring is concerned everything was plug and play to the tac module and the pedal. The only thing that is not connected are the wires for cruse control. I left them on the plug, but have not connected them to the Nissan harness, because I haven't figured out which wires to tap in to. Should I check these wires and possibly pull them from the tac plug?
12-16-2009, 09:10 AM
#6
What is your FP set at?
I had some similar issues on my ls swap, but it was due to the rubber hose in the tank blowing out, and only giving me 24 lbs of FP....... that just wasn't going to cut it apparently! LOL
Also, there isn't an issue running an F-body tune with the DBW? F-bodies never had DBW, so thats why I ask..... I really have no idea honestly.
good luck with it!
-jason
I had some similar issues on my ls swap, but it was due to the rubber hose in the tank blowing out, and only giving me 24 lbs of FP....... that just wasn't going to cut it apparently! LOL
Also, there isn't an issue running an F-body tune with the DBW? F-bodies never had DBW, so thats why I ask..... I really have no idea honestly.
good luck with it!
-jason
12-16-2009, 09:21 AM
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Well, I don''t have a fuel pressure gauge to consistenly monitor it, but I did rent one a couple of months back and the gauge was showing my fuel pressure at 58psi at the the rail. I'm running a corvett fuel filter/regulator so I should be holding steady at that 60-58psi mark.
Yeah, I've heard that some have had issues with the F-body tune on the truck PCM's.
Yeah, I've heard that some have had issues with the F-body tune on the truck PCM's.
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12-16-2009, 09:50 AM
#8
Are you using and F-body 6 speed tranny harness?
Did the 5.3 have an auto?
Has the TAC wiring been tied into the ECM correctly?
Is the f-body tune for an auto or 6 speed?
Sounds to me like you are crossed up between using DBW on a DBC setup, and you car is in limp mode, as it can't see the difference.
With the engine off, key in the on position, does the throttle body respond to the gas pedal at all?
T,
Did the 5.3 have an auto?
Has the TAC wiring been tied into the ECM correctly?
Is the f-body tune for an auto or 6 speed?
Sounds to me like you are crossed up between using DBW on a DBC setup, and you car is in limp mode, as it can't see the difference.
With the engine off, key in the on position, does the throttle body respond to the gas pedal at all?
T,
12-16-2009, 10:05 AM
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Are you using and F-body 6 speed tranny harness?
Did the 5.3 have an auto?
Has the TAC wiring been tied into the ECM correctly?
Is the f-body tune for an auto or 6 speed?
Sounds to me like you are crossed up between using DBW on a DBC setup, and you car is in limp mode, as it can't see the difference.
With the engine off, key in the on position, does the throttle body respond to the gas pedal at all?
T,
Did the 5.3 have an auto?
Has the TAC wiring been tied into the ECM correctly?
Is the f-body tune for an auto or 6 speed?
Sounds to me like you are crossed up between using DBW on a DBC setup, and you car is in limp mode, as it can't see the difference.
With the engine off, key in the on position, does the throttle body respond to the gas pedal at all?
T,
The 5.3 had an Auto. From what I understand, all the 5.3L's were auto. The tune is for the 6 speed. As far as I know, the TAC wiring is all correct, but I really have no way of verifying. I used the pinouts from this site as well as LT1swap.com to rewire the harness. When the engine is off, key in the on position, the throttle body does respond normally.
I will take another look at the fuel setup. When I bought this car the shell had sat for 4 years so it had 4 year old gas in it. I bought a brand new Walbro fuel pump and grabbed a bucket, put some juice to the fuel pump and pump out all the old gas. Right now there's about 4 gallons of new gas in the tank, but there may have been some old gas still in there that has mixed in. As soon as I get it running I will take it to the gas station and fill up with 91 octane so I can start my seafoam treatment on the tank and engine.
