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LS1 First Start Attempt....


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....and no cigar. Tried to start it up for the first time yesterday. Engine turns over, has good fuel pressure to the fuel rails, but no spark and no fuel from the injectors. Car has the stock PCM (reflashed from auto to 6-spd), stock body control module, stock Camaro wiring harness (with some modifications to shorten or lengthen wires), Camaro steering column with chip reader and matching key. When the computer was reflashed I had them disable the VATS and some other minor stuff. Our first guess is that no spark and injectors sounds like a VATS issue, but it shouldn't be. I thought I'd ask for help here before I spend hours and hours in the service manual. Maybe this problem will be familiar to someone...

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I don't know if this will help or not but on the LS2, the power to the coils comes in to a plug near the MAF plug. In the stock car it routes around the front of the car with the light harness and then from the front near the radiator. I would not have known when wiring mine up except for MAS280. He has lots of experience with the LS1's too, you might PM him.

Mike

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Yup, coilpacks are plugged in. We checked all the sensors, fuses, relays, and they're all plugged in, fusing, and relaying.

 

The steering column actually fits good. It required shortening the shaft in the Camaro column, and welding on the steering knuckle from the Datsun Column. Inside the car, the column had to be spaced down by about 3/4 inch so all the connectors and lock mechanisms would clear the column mount. The neat part is that all the column controls work. I used the Camaro wiper motor (basically a bolt in and functional intermittant wipers!), the Camaro fog lights, and horns. The dashboard is still out of the car, but when it's all togethe I'll send a picture.

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Yup, coilpacks are plugged in. We checked all the sensors, fuses, relays, and they're all plugged in, fusing, and relaying.

 

The steering column actually fits good. It required shortening the shaft in the Camaro column, and welding on the steering knuckle from the Datsun Column. Inside the car, the column had to be spaced down by about 3/4 inch so all the connectors and lock mechanisms would clear the column mount. The neat part is that all the column controls work. I used the Camaro wiper motor (basically a bolt in and functional intermittant wipers!), the Camaro fog lights, and horns. The dashboard is still out of the car, but when it's all togethe I'll send a picture.

 

Bummer about not starting. Sorry I can't offer any suggestions, never played with an LSxx. I did have a similar issue with my LT1 Z28 that turned out to be a coil wire and the ignition module that just decided to die.

I am also very interested in the steering column install. I pulled mine out of my '94 Z28 donor and was wondering how tough it would be to adapt. Tilt and all the controls would be nice. My plan is to use the Z28 dash and controls along with most of the body wiring, I pulled out the wiring today, OMG there is a ton of this stuff. Hopefully I can figure this all out, there must be 15 relays involved in there. I was also looking at the wiper assemby, good to hear it will work.

Good luck with the engine debug.

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... The neat part is that all the column controls work. I used the Camaro wiper motor (basically a bolt in and functional intermittant wipers!)...when it's all together I'll send a picture.

 

Not to change the topic, but that's awesome if you were able to just bolt in a Camaro wiper motor like a retrofit. If you post a pic of that, I'll find the thread regarding the wiper motors and add it to that. Thanks for the info.

 

Davy

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The service manual says the same thing about the crank sensor. It also says that any problems with the crank sensor and cam sensor won't throw a code, which is exactly what's happening here. I'm sure I plugged it in, but maybe there's a broken wire or something. I plan to do a continuity check on the wires for both sensors tonight.

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Still need some help....

I've gone thru the service manual 'Cranks but won't start' troubleshooting page and still have the problem. I've checked all the cam and crank sensor wires for continuity and shorts to ground and they check out as good. I've replaced the crank sensor and the engine coolant sensor. All the PCM grounds check out good. The other grounds are all in place. I have a fuel enable signal from the BCM. All the fuses are good. I pulled the MAF connector to run on stored code and that made no difference. I tried the PCM from this car in my Camaro and it fired right up, so I know the PCM is good. The key issue is that there's still no rpm signal from the crank sensor. Is there a way to test the crank sensor with a meter since I don't have access to a dealer scan tool? I'd like to know for sure I didn't get a defective one from the auto parts store. What am I missing???

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This is stolen from a site some of the RX7 swappers will recognize (swapcartech.com), and I'm sure you have tried this, but it may help others go through the troubleshooting systematically. Hope you find the answer.

 

 

 

 

Ignition/Spark Troubleshooting. LS1

 

 

- First things first, make sure all sensors are plugged in. The Cam sensor and the Crank sensor both are directly related to spark. Without them, you will have none. The cam sensor is the sensor located behind the intake mani on the black. It is just below the map sensor. The crank position sensor is located behind the starter and is a bear to get to. Easiest way to plug that in is to remove the starter (2 bolts).

 

- Now that you are sure your sensors are all plugged in, check your grounds. There are three grounds that come off the ls1 harness at the rear of the drivers side fuel rail. These all need to have a solid ground. Check the ground coming off your battery as well. Be sure all paint is removed from where it's grounded. Next you must make sure that your engine block is grounded. All the sensors use the engine block as a ground. Also check your ground that you made at the passenger footwell coming off the harness.

 

- Now you have all the sensors plugged in and everything grounded. Next is power. There are two sources of power you need, ign-on and 12 volts constant. We will start with 12 volts constant. You will need to get a voltmeter out and check that this is getting power to it. They are pins Blue 20 and Blue 57 and these must be 12 volts at all time. The function of the 12 volt constant is to keep the PCM volital memory alive, so it does not have to go thru the relearn cycle. If this wire is not getting any voltage, run a wire directly to the positive battery terminal, be sure to put a fuse inline (5 amps is fine). The wire you will be testing is orange. The next power source is the 12 volts ign-on wire. This is the pink wire coming from your harness in the passenger footwell. The power for relay coils, igniters, sensors, etc. comes from this wire. This is pin 19 blue connector on your harness. You must test this with the ignition switched on. If you get voltage when it is switched on, you are fine. If not, find a wire that is hot only when the ignition is on and remains hot while cranking.

 

- Now you have power, ground, and all sensors plugged in. Now go back and check for the following:

- 12v going to blue 20 and blue 57

- pins 1 and 40 are grounded on both blue and red

Easiest way to check this is to unplug the pcm, if you have not already, and test from there. I've found that sticking a paper clip in the pin and touching the paper clip is the easiest way for this.

 

- Now you are fine the way of power and grounds going to the pcm. Next is the coils. To test that power is getting to the coils properly, you must measure the pink wire going into each main coil pack connector. There are two of these connectors, one on each bank. This shuold be 12 volts with ign-on and no lower than 10 volts while cranking. If this tests out, you now know that the coil packs are getting power (the pink wire you tapped into ign-on is working properly)

 

- Now you have power, ground, sensors plugged in, and power to your coils with and without cranking. Next you need to test your plug wires. Simple way to do this is to test for continuity through them. This problem is the least likely to have happened.

 

- If, at this point, you have no spark still, something else is wrong. You have assured that your pcm is getting the proper power. You need to check that your pcm is still alive. All pcm's from 1999+ in the f-bodies can be swapped out. 1998 is on it's own. Take your pcm into an f-body that matches and test it int here. You cannot hurt the car by doing this. If the car starts, then your pcm is fine. If not, then you know where your problem lies. Do not try someone elses pcm in your car, try yours in their car first.

 

- If the pcm does work, check power from the sensors. You will need to look up your specific pcm pin layout and see where the sensor is feeding the pcm. If your sensor is dead, this is the way to tell. It must be giving you some feedback (cam or crank). If not, there is your culprit.

 

- If after all that, you still are getting no spark....something very odd has happened. Theoretically you should be up and running at this point. Make sure that you do, in fact, not have spark. Pull the plug end of the plug wire off and stick a screwdriver in it. Place it near a ground, then crank. There should be a spark in between the two. If you do have spark, start checking for fuel related issues. If no spark, look over everything again.

 

 

 

 

 

So from what I've read so far, try to steal a cam and crank sensor from your friend with the f-body. He'll never know what hit him. :)

__________________

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