Cranks but no start. Need help please

[rajesh717]

NEED HELP PLEASE.

I am having difficulty troubleshooting my car Cranks but no start condition.

My water pump was leaking so replaced with new water pump and also installed new oil pump because i always had low oil pressure on my dash when ever the car was in operating temp.

I actually cranked my car without serpentine belt before removing anything just to check something. Engine started fine, i repeated the process few times for the third time it hesitated to start. I thought it will be once i install everything back on.

Replaced new water pump and also Oil pump. Opened head also just to clean everything made sure all valves are good and pistons also.

Put everything back on but the car never stared. It cranks fine but never starts, I checked compression it has 100-90-90-90 in 4 cylinders respectively.
Checked all sparks and wires, There was Spark from each plug every time i crank engine.
Checked fuel injectors, Cranked car disconnecting Ignition coil all the injectors sprayed very fine according to timing.
Checked crank sensor it seems to be working because if it is bad it wont allow sparks or fuel but them both are fine.
I inquired with local mechanic if compression is the issue but he said car should start with that readings.

Please need suggestions because this the only car i have and i make money on delivering Pizzas. Car is in driveway for 3 weeks now. Not able to work renting a car and its very expensive.

Thanks in advance

[avguy]

.... also installed new oil pump because i always had low oil pressure on my dash when ever the car was in operating temp.....

Are you certain the oil pressure was actually low, and not just a case of a bad sender? If oil pressure was truly low enough to set the oil light on, then this engine is highly likely to completely fail in the near future.

..... I checked compression it has 100-90-90-90 in 4 cylinders respectively. ....

That's WAY too low - about half of what it should be, and there's no sense in continuing to try to start it because it's not going to run well in any case. Review the timing and figure out what's wrong.

[rajesh717]

Are you certain the oil pressure was actually low, and not just a case of a bad sender? If oil pressure was truly low enough to set the oil light on, then this engine is highly likely to completely fail in the near future.


That's WAY too low - about half of what it should be, and there's no sense in continuing to try to start it because it's not going to run well in any case. Review the timing and figure out what's wrong.

Thanks a lot for responding to my post. Can you tell me how much pressure it should have to start the car. If there is a leak, I believe there wont be any compression. I was wondering why the engine wont start. M not worries about it running lean or richbut i do not understand why it wont startin first place.

[avguy]

There's not one magic compression number, above which it will start. The timing can be wrong in a number of different ways, depending on which of the 3 pulleys are off and in what direction(s). And because the cam and crank sensors are out of synch, there's a good chance the plugs are firing at the wrong time (just a bit off is all it takes).

And regarding 'no compression', you're situation is likely to be one or two valves per cylinder almost, but not completely closed when they should be. And because not everything can exit out of those tiny gaps all at once, that's why partial compression is happening.

[rajesh717]

There's not one magic compression number, above which it will start. The timing can be wrong in a number of different ways, depending on which of the 3 pulleys are off and in what direction(s). And because the cam and crank sensors are out of synch, there's a good chance the plugs are firing at the wrong time (just a bit off is all it takes).

And regarding 'no compression', you're situation is likely to be one or two valves per cylinder almost, but not completely closed when they should be. And because not everything can exit out of those tiny gaps all at once, that's why partial compression is happening.

Thanks for your response again. Can you please guide me how to re synchronis cam and crank sensors please?? I checked timing gear markings atleast 10 times and every time they were spot on (i checked them bu manually rotating crank pulley).

The tensioner pulley is also in right tension according to the arrows. In this case do you think cam sensor is bad??
Thanks in advance

[avguy]

Sorry but you're misunderstanding what I'm saying about the crank/cam sensors. They would be out of synch only because of a timing loop issue, not faulty by themselves. The low compression that you posted is what I'm focused on, and is indicating that some issue is going on with the engine.

However, I made the assumption that your vehicle was running well before the water pump was replaced, and could not have had compression that low. I also assumed that the compression test was done correctly, and that the compression tool is reasonably accurate. If any of those assumptions is wrong, then naturally I'm barking up the wrong tree.

So if all of the above are true, then there's virtually no possibility other than a timing belt loop issue for such low compression. Did you torque the 3 WP Allen bolts properly? That's something that has bitten a few folks in the butt over the years. How about the harmonic balancer - what method did you use to torque it? One member here didn't torque it properly and had it loosen up, with the inevitable disastrous outcome.

[rajesh717]

Sorry but you're misunderstanding what I'm saying about the crank/cam sensors. They would be out of synch only because of a timing loop issue, not faulty by themselves. The low compression that you posted is what I'm focused on, and is indicating that some issue is going on with the engine.

However, I made the assumption that your vehicle was running well before the water pump was replaced, and could not have had compression that low. I also assumed that the compression test was done correctly, and that the compression tool is reasonably accurate. If any of those assumptions is wrong, then naturally I'm barking up the wrong tree.

So if all of the above are true, then there's virtually no possibility other than a timing belt loop issue for such low compression. Did you torque the 3 WP Allen bolts properly? That's something that has bitten a few folks in the butt over the years. How about the harmonic balancer - what method did you use to torque it? One member here didn't torque it properly and had it loosen up, with the inevitable disastrous outcome.

Trust me the car was running like a champ before replacing water pump. This is not my first time opening head on this car. I replaced all mew valves in the past when timing belt broke. It broke twice and every time it started back on in just one turn bit this time its strange and its not timing belt but just water pump. I torqued all the bilts according to vehicle specs. I used angular torque torque 60-60-60-10 after torqueing headbolts to spec. Harmonic balancer was perfectly fitted also.

[rajesh717]

I am renting compression tool from autozone which is about 50 bucks. The results i posted were dry test on cold start. Wet test was around 130psi and above on each cylinder.

[avguy]

The compression on my '05 was 200 PSI across the board (dry), so that's the primary reference I'm using to give you my opinion. In addition, another member with a different issue was reporting compression of 160, and I suggested that was a bit lower than it should be. He eventually rechecked the timing and found it to be one tooth off. Once corrected his compression went up to 190+.

I can't imagine what might have gone wrong with your work, but really feel that something is not right in the timing belt loop. But that's JMHO and this is your vehicle, so it's obviously up to you on how to proceed.

[rajesh717]

The compression on my '05 was 200 PSI across the board (dry), so that's the primary reference I'm using to give you my opinion. In addition, another member with a different issue was reporting compression of 160, and I suggested that was a bit lower than it should be. He eventually rechecked the timing and found it to be one tooth off. Once corrected his compression went up to 190+.

I can't imagine what might have gone wrong with your work, but really feel that something is not right in the timing belt loop. But that's JMHO and this is your vehicle, so it's obviously up to you on how to proceed.

First of all I appreciate your time and kindness for trying to help me. I will go ahead and re install the timing belt just to make sure and will update you.