Won't start after cam install

**Bedwards** · 05-30-2011

Originally Posted by scottydoggs

did you change springs or push rods or anything like that? what cam did you put in? did the cam spin freely when installed? im so reaching here....

the good news is im sure bill boost will be back tomorrow, he's got all the answers lately, link it to test bill boost maybe.

Changed the valve springs and retainers to the G8 ones. I have a VS cam in it.

Originally Posted by GR8racingfool

Sounds to me that the engine is not in time. Cylinder #1 needs to be at TDC first, and the timing dots lined up before you remove the old to install the new. With out moving the crank, install the new, and line it up, and BEFORE installing the lifters, and push rods, you want to rotate the crank around 5 or 6 times making sure each time the dots line up perfect each time around and when #1 meets TDC.

I think your off a tooth with the back fire, meaning your intake valve(s) are probably open when they should be closed.

But before you go tearing back into it, make sure the cam and crank sensor are hooked in. I would seriously fix the cam sensor connector. I would go to a junk yard, and cut one off the engine loom, and cut and splice it in, solder it, and seal it with heat shrink, and then recover it in the loom for protection. You NEED those clips on there to keep the connection.

~F~

Wont cylinder 1 be at TDC, when the timing dot is at the top? I was told to just line up the timing dots, and then the camshaft and crankshaft will be timed properly. I wonder if it misaligned by a tooth or something, once I got it installed. Is one tooth off enough to cause this serious of a problem?

**Bedwards** · 05-31-2011

I'll probably pull the front cover today and see if the timing marks are lined up.

**NegativeOne13** · 05-31-2011

If your off one tooth, it might start, but won't run for ****.

**BillBoost37** · 05-31-2011

One tooth off won't make a difference for starting.

One suggestion I make to everyone is take pictures of teh gears and dots. Always. That way you never question yourself if something goes wrong.

Gotta go back and reread the thread to see what you've tried so far.

**BillBoost37** · 05-31-2011

Ok, let's see. Assume your timing is ok on the gear unless it turns to a point a binds. Binding would be bad.

Check for spark, got that ...good.
Take a piece of vacuum line and run it off the metal nipple under the SC on the LIM. Put the straw of a can of brake cleaner in there and have someone crank the car.. do a few short bursts of brake clean. Does it run? Does your shooting brake clean help it start? If yes..check the maf. a bad maf can turn off the injectors.

Crank sensor is plugged in? Pull the connector and inspect with a mirror for any bent pins. Check the ICM connector. Should be snug.

**BillBoost37** · 05-31-2011

Have you pulled the plugs and found them wet with fuel? That would mean it's getting fuel.

Any luck testing for spark?

At startup our ICM controls everything. It sets timing to 10 degrees, fueling is X and it's tough to get our cars not to start. So it'll be easy enough.

Another couple of things that could keep us from starting. When you pull the motor, you have to pull the negative cable at the lowest trans to engine bolt/stud. There are two small wire grounds and the negative cable. It's possible for those two little guys to hide. Make sure you have all three on the stud and that nut is at least snug.

**Bedwards** · 05-31-2011

Originally Posted by BillBoost37

Ok, let's see. Assume your timing is ok on the gear unless it turns to a point a binds. Binding would be bad.

Check for spark, got that ...good.
Take a piece of vacuum line and run it off the metal nipple under the SC on the LIM. Put the straw of a can of brake cleaner in there and have someone crank the car.. do a few short bursts of brake clean. Does it run? Does your shooting brake clean help it start? If yes..check the maf. a bad maf can turn off the injectors.

Crank sensor is plugged in? Pull the connector and inspect with a mirror for any bent pins. Check the ICM connector. Should be snug.

I'll try the brake clean thing tonight. The crank sensor is plugged in but I havent inspected the pins yet. The ICM connector is snug.

**Bedwards** · 05-31-2011

Originally Posted by BillBoost37

Have you pulled the plugs and found them wet with fuel? That would mean it's getting fuel.

Any luck testing for spark?

At startup our ICM controls everything. It sets timing to 10 degrees, fueling is X and it's tough to get our cars not to start. So it'll be easy enough.

Another couple of things that could keep us from starting. When you pull the motor, you have to pull the negative cable at the lowest trans to engine bolt/stud. There are two small wire grounds and the negative cable. It's possible for those two little guys to hide. Make sure you have all three on the stud and that nut is at least snug.

Plugs were wet with fuel. I do have spark, I did test it. I hooked up those ground wires to that transmission stud, but I should double check to make sure the nut is snug.

**BillBoost37** · 05-31-2011

Skip the brake cleaner. That was to test for fuel. Wet plugs = fuel.

**Bedwards** · 05-31-2011

Originally Posted by BillBoost37

Skip the brake cleaner. That was to test for fuel. Wet plugs = fuel.

Okay. What about that camshaft position sensor connector? Could that cause this?

**matt5112** · 05-31-2011

if you have fuel and spark, does it have air?

**BillBoost37** · 05-31-2011

Cam postion sensor could be the cause. If it's unhooked you have a 1 in 6 chance the motor will start. However I've never seen one cause it to run badly like you mentioned.

**Bedwards** · 05-31-2011

Originally Posted by matt5112

if you have fuel and spark, does it have air?

There's no vacuum leaks that I can see.

**BillBoost37** · 05-31-2011

You'd have to have something like the EGR tube off (if not blocked) or the brake booster for that big of an issue.

**alkygto** · 05-31-2011

Originally Posted by matt5112

if you have fuel and spark, does it have air?

Seriously, some good help here. Glad to see it.

**Bedwards** · 05-31-2011

I'm going to replace the ICM harness tomorrow and see if that does anything.

**Bedwards** · 05-31-2011

Just wondering, if a MAF sensor got wet, could it cause a no-start issue?

**Tea Time** · 05-31-2011

i wouldn't think so...unplug it and see if the car runs...it'll run poor for a minute unplugged but will come out of it.

**benner** · 05-31-2011

Just a though but have you unplugged the MAF and tried starting it? It'll switch over to speed density tables if no maf is showing. Won't run as good but it'll still run.

Also I've seen some pretty stupid **** happen like a rag being left in the intake and plugging it.

Edit. Tea time beat me to it.