motor wont start...
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Teching In
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Ok so here is what I found out tonight. I looked at all fuses and relays under the hood and all is good. I tested the coil and when I checked continuity from ground on coil#3 to ground on body it was good. So there for I know my grounds are good. On the coil the pink wire terminal D has 12volts but when I tested for volts on terminal C when cranking the engine it only gives .7volts... is that right? How many volts should terminal c be reciving?
It sounds like all your wiring is correct and working properly.
The trigger voltage from the PCM to terminal C is variable. I'm not sure what the range of this voltage should be.
New questions:
Before installing this engine in the vehicle, how did the previous engine run? What PCM are you using? The same one that ran the original engine?
Maybe it's time to grab an F-Body PCM from somewhere and swap it in to see what happens.
The trigger voltage from the PCM to terminal C is variable. I'm not sure what the range of this voltage should be.
New questions:
Before installing this engine in the vehicle, how did the previous engine run? What PCM are you using? The same one that ran the original engine?
Maybe it's time to grab an F-Body PCM from somewhere and swap it in to see what happens.
Thread Starter
Teching In
Joined: Jul 2010
Posts: 31
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The engine befor it was running great nothing wrong with anything or the computer. When I put the motor in I had my friend put the starter in and he hooked the starter up wrong. It smoked when I hooked the battery up so hereing that what do u think? Computer?
You verified the timing chain, right? Dot to dot?
What smoked?? the starter or the PCM?? If the PCM smoked, you best get that thing out of there right away and swap in another.
This might also be another really stupid question (because I don't know a whole lot about the LQ4), but is the teeth number on the crank the same amount that is setup for the PCM?
Keep us updated.
What smoked?? the starter or the PCM?? If the PCM smoked, you best get that thing out of there right away and swap in another.
This might also be another really stupid question (because I don't know a whole lot about the LQ4), but is the teeth number on the crank the same amount that is setup for the PCM?
Keep us updated.
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Verdad Gallardo Wow this sucks. Bring the car over. Wait, no...
Where did this LQ4 come from? A running vehicle? I'm now suspecting the crankshaft and camshaft sensors themselves. BOTH must be working, connected and sending a good signal to the PCM to get ignition coil trigger signals. Are these the ones that came with this engine or did you swap the original ones from your LS1?
Both these sensors from both engines should be black.
As you said the (LS1) engine in this car was running before you pulled it, I'll suggest you take those two sensors and install them on the LQ4 engine.
Where did this LQ4 come from? A running vehicle? I'm now suspecting the crankshaft and camshaft sensors themselves. BOTH must be working, connected and sending a good signal to the PCM to get ignition coil trigger signals. Are these the ones that came with this engine or did you swap the original ones from your LS1?
Both these sensors from both engines should be black.
As you said the (LS1) engine in this car was running before you pulled it, I'll suggest you take those two sensors and install them on the LQ4 engine.
As stupid as this sounds, you need to confirm the following fuses are good (as well as all the others):
Under hood fuse and relay block 1:
-PCM BAT
Under hood fuse and relay block 2:
-ENG SEN
-PCM IGN
-STRTR
-PCM IGN
-IGN
-IGN
Don’t just pull and look at them. With the ignition key in the "on" position, probe them with a test light while they’re installed. You should get power on both ends of each fuse.
I say check all this as the PCM has several fused power feeds, not just one.
The camshaft sensor is behind the intake manifold so I hope you find the problem before getting to it.
Under hood fuse and relay block 1:
-PCM BAT
Under hood fuse and relay block 2:
-ENG SEN
-PCM IGN
-STRTR
-PCM IGN
-IGN
-IGN
Don’t just pull and look at them. With the ignition key in the "on" position, probe them with a test light while they’re installed. You should get power on both ends of each fuse.
I say check all this as the PCM has several fused power feeds, not just one.
The camshaft sensor is behind the intake manifold so I hope you find the problem before getting to it.
Last edited by Paul Bell; Jan 14, 2011 at 08:34 AM.
Thread Starter
Teching In
Joined: Jul 2010
Posts: 31
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Hey everyone! The motor started today!!! I found out what it was. The b+ wire to the crankshaft was fried and the computer also got fried. I ran a new b+ wire and put in a new ECU and it started
thanks to all of y'all. I really appritiate everything
thanks to all of y'all. I really appritiate everything 
