b3av3r

iTrader: (3)

I have an 01 SS. I swapped my motor with an ls1 out of an 01 WS-6. I used the computer from the new motor instead of reusing my computer after I verified with my tuner that it would work and he could take care of the VIN issue.

After we got everything installed and plugged in we fired the car up. Everything seems to work perfect except for my tach. I haven't driven the car yet just fired it up to check for any major problems, leaks, etc.

My oil pressure and temp gauge both work, not sure of the speedo or fuel just yet but I would assume they work as well. I checked all of the fuses that could possibly be related and of course they are all good.

I am not exactly sure where to go with my troubleshooting at this point. Any suggestions on what to look for or where to begin would be appreciated.

Thanks

the_merv

iTrader: (88)

There is a wire in the Harness that goes from the PCM to the Tach..maybe it's got a bad connection. Did you use your same Engine Harness?

b3av3r

iTrader: (3)

no I used the engine harness that was with the new motor.

so the tach signal is sent straight from the pcm to the gauge cluster? I will pull up the pin assignments and check that one out. I know the tach worked when I parked it before the engine swap so that seems the culprit.

bigfatls6

iTrader: (34)

My buddys 99 did that when he swapped in a lq4 and found out that they did not plug in the front plug by the passengers side head. Fromwhat I was told it is for the cam sensor I think.

bigfatls6

iTrader: (34)

My buddys 99 did that when he swapped in a lq4 and found out that they did not plug in the front plug by the passengers side head. Fromwhat I was told it is for the cam sensor I think.

the_merv

iTrader: (88)

The Cam Sensor is on back of the Block right behind the Intake in the Center.

bigfatls6

iTrader: (34)

I am pretty sure his was on the front. I think he had one in the front and back. They had the back one pluged in but not the front one. As soon as he plugged it in bingo his tach worked fine. His would also be hard to start some ttimes though and he would have to jsut switch it off and try again and it would start fine. When it wouldn't start it would pop like it was back fireing.

edcmat-l1

iTrader: (10)

That's exactly what happens when the cam sensor's unplugged. It's kinda hard to start.

BTW, LS1 in the back. LS2/7, LQ9 in the front.

Tach is driven by the cam sensor signal.

the_merv

iTrader: (88)

You must be thinking of the newer ones, cause I can show you plenty of LQ4/LQ9 Blocks that have it in the top center.. I have one of them under my Hood.

edcmat-l1

iTrader: (10)

OK, my bad. I could have swore they were up front on the timing cover, same as the LS2/7.

b3av3r

iTrader: (3)

if the cam sensor were unplugged would it idle or run rough?

the motor seemed to run perfect and had a nice smooth idle as well

edcmat-l1

iTrader: (10)

It makes them harder to start, but once running, there's no difference.

the_merv

iTrader: (88)

I'm suprised it would fire, I thought the Cam Sensor told it what side of the Cam it was on so it can fire that Cylinder..

bigfatls6

iTrader: (34)

His car is a 99 camaro z28 hard top and it was definetly in the front. The plug that was unpluged was right by the passenger side head on the front of the engine. The car would be hard to start and you could try it a couple of times and then it would start right up and run fine couldn't tell. He drove it like that fro about a month before we figured it out. The tach completely quit. He thought the plugs were for the AIR that was removed from the car.

Op check on the front of your engine and if there is any thing unpluged plug it in.

the_merv

iTrader: (88)

^^I want to see a pic of what you mean.. I wonder what you are talking about..lol

edcmat-l1

iTrader: (10)

Cam sensor is only to synchronize the sequential fuel injection. If it doesn't see a cam signal, it will randomly fire the injectors. That's why it will pop and sound funny, but if you turn the key off then back on it will start.

Edit: LS1, the cam sensor is in the rear, behind the intake.

the_merv

iTrader: (88)

The only thing I can think of by the Passenger's side Head is the EGR..and the MAP on the L76/LS3 Intake..not too sure about the LS2..

ak95ta

iTrader: (3)

Hey, you must be thinking of your swap, where it uses the tach out wire. 99 and newer cars send the tach signal via the serial line to the cluster. There is a tach out on the LS1 pcm, but it goes to the EBCM unit, not to the cluster. In lt1 to ls1 swaps, that wire is sent to the cluster. So to the OP, I doubt you have it wired wrong, check the sensor as stated above.

the_merv

iTrader: (88)

^^I have that Tach out wire on the LS1 PCM, I used a 1999 Harness..
I just made it go directly to the Cluster since my 1995 is still Analog and has no BCM.