PCM issues
Oct 1, 2013 | 10:35 AM
#1
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PCM issues
I live in South Africa and have just finished building in an LQ9 engine into a Nissan Patrol Y61 or GU with original manual gearbox. I got the engine with a Delphi PCM and wiring harness from SSP.
It starts perfectly on high idle but when reaching temperature the idle drops and starts hunting. The harness has been supplied with the large round plug for auto transmission and a plug for for VSS and are not being used.
I have had the vehicle to my local supplier where they found the PCM program to be for a 5.3. They have managed to get the engine to idle but it nearly stalls before settling down to idle. Which vehicle PCM program should they use considering I am using standard Nissan manual gearbox. They don't find a manual program and have downloaded some program and is running extremely rich on idle. I was towing a 1500 kg load which returned a consumption of 30 liters per 100km. (12.5 gal / 100 miles)
Can anyone please advise before I take it back for them to try and sort out
It starts perfectly on high idle but when reaching temperature the idle drops and starts hunting. The harness has been supplied with the large round plug for auto transmission and a plug for for VSS and are not being used.
I have had the vehicle to my local supplier where they found the PCM program to be for a 5.3. They have managed to get the engine to idle but it nearly stalls before settling down to idle. Which vehicle PCM program should they use considering I am using standard Nissan manual gearbox. They don't find a manual program and have downloaded some program and is running extremely rich on idle. I was towing a 1500 kg load which returned a consumption of 30 liters per 100km. (12.5 gal / 100 miles)
Can anyone please advise before I take it back for them to try and sort out
Oct 1, 2013 | 03:22 PM
#2
What are you using to tune the PCM ? Hp tuners or EFI live
If u give some details on your lq9 build I am sure somebody has a tune that will get you close and you can tune from there.
If u give some details on your lq9 build I am sure somebody has a tune that will get you close and you can tune from there.
Oct 2, 2013 | 04:28 AM
#3
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I have long tube headers (4 into 2 into 1) with the O2 sensor bungs on the 2 into 1 'Y' piece. Running only the front sensors. The two '1's go into a single 31/2'' pipe exiting at the rear. As mentioned before, the program supplied is for a 5.3. Will the MAF and O2 sensors need to be changed to match the correct program? Is the VSS required to enable the program to function correctly. I am not able to use the auto trans and VSS plugs which are part of the harness.
Oct 2, 2013 | 04:29 AM
#4
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The LQ9 is a rebuilt engine from the USA and the wiring harness and PCM supplied by SSP (USA) for LS1 and Vortec engines. I have built the engine into a 2005 Nissan Patrol 3.0 turbo diesel wagon. This is a 4x4, 4 door with double rear doors weighing 5200 lbs. The gearbox is the original 5 speed manual Nissan one.
I have long tube headers (4 into 2 into 1) with the O2 sensor bungs on the 2 into 1 'Y' piece. Running only the front sensors. The two '1's go into a single 31/2'' pipe exiting at the rear. As mentioned before, the program supplied is for a 5.3. Will the MAF and O2 sensors need to be changed to match the correct program? Is the VSS required to enable the program to function correctly. I am not able to use the auto trans and VSS plugs which are part of the harness.
I have long tube headers (4 into 2 into 1) with the O2 sensor bungs on the 2 into 1 'Y' piece. Running only the front sensors. The two '1's go into a single 31/2'' pipe exiting at the rear. As mentioned before, the program supplied is for a 5.3. Will the MAF and O2 sensors need to be changed to match the correct program? Is the VSS required to enable the program to function correctly. I am not able to use the auto trans and VSS plugs which are part of the harness.
Oct 2, 2013 | 04:42 AM
#5
That's cool to hear of 6.0s running around South Africa , cool !
Def sounds like a closed loop problem , I had a similar problem on my 6.0 van recently , turned out it was a faulty o2 sensor .
Can you scan the engine when it's stumbling for us ? Would like to see what your oxygen sensors are reading when it's stumbling .
Have you checked for vacuum leaks ?
Def sounds like a closed loop problem , I had a similar problem on my 6.0 van recently , turned out it was a faulty o2 sensor .
Can you scan the engine when it's stumbling for us ? Would like to see what your oxygen sensors are reading when it's stumbling .
Have you checked for vacuum leaks ?
Oct 2, 2013 | 06:02 AM
#6
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That's cool to hear of 6.0s running around South Africa , cool !
Def sounds like a closed loop problem , I had a similar problem on my 6.0 van recently , turned out it was a faulty o2 sensor .
Can you scan the engine when it's stumbling for us ? Would like to see what your oxygen sensors are reading when it's stumbling .
Have you checked for vacuum leaks ?
Def sounds like a closed loop problem , I had a similar problem on my 6.0 van recently , turned out it was a faulty o2 sensor .
Can you scan the engine when it's stumbling for us ? Would like to see what your oxygen sensors are reading when it's stumbling .
Have you checked for vacuum leaks ?
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