Weird problem when turning over when cold.

[loydracing]

Hey guys! Ok I have a strange thing happening and it seems like it's bad for my engine. I have searched and came up with nothing at all. So here is what's happening. When it's really cold out like around 0* and I'm turning it over it will turn smoothly for about a second, then it makes a sound almost like the timing is off and valves are contacting the pistons. It will briefly stop cranking for roughly half a second, almost seems like the compression is pushing the crank the wrong direction because when it does it it makes a popping sound and almost sounds like the engine "back spins" for a second but if I stay on the key and keep it turning over it will start. It takes about 2-3 seconds to start when it's really cold and it will do what I described one to two times during cranking. I know the timing is dead on because I did it myself and the car runs great otherwise. Compression is 140psi +- 10 across. 6 bolt block, 2g head. 95 tsi awd. Thanks guys I just can't really come to a conclusion on what's going on and I'm hoping someone can enlighten me a bit. I'm just worried something's hurting my motor and it's my dd so I can't afford to break it!

 

[okcummins]

I would start with checking the battery. I believe Auto zone will check it for free. If it checks good my next suspect would be the starter. Make sure you have good clean connections also.

 

[loydracing]

The starter was my first thought, but it just sounds like something more serious. I forgot to mention it in my first post but when that happens it sort of sounds like opening a can of soda and it blows a decent amount of air back out of my air filter it's enough to blow out a cigarette lighter! I do have a couple starters in my shop, I'll throw one in tomorrow evening and see what it does.

 

[Breezio69]

Pretty much the only way for air to come back through the intake tract the wrong way is a broken or bent intake valve or valves. That would explain why you think you hear valve to piston contact. You hear it and know it, but you dont want to believe it.

I would triple check the timing, followed up with a leak down test.

 

[loydracing]

Yeah haha the last thing I want to do is tear it down again, but if it's internal damage like that it has to be done! I have never done a leak down test on it before so that's a good idea! I'm not sure why I didn't think of that so thank you for reminding me. I'm still going to install the starter today though just cause the one on it now has 220k plus on it.

 

[Breezio69]

Its the only thing that makes sense, and not just with our cars, any car that blows air the wrong way has some head issues.

 

[okcummins]

I would check you timing belt tensioner. I have seen a car run with a bad tensioner and it never jumped time but the belt was flapping around every time it fired. If your getting good compression numbers I would say you don't have bent valves.

 

[1G Eclipse94928]

I would check you timing belt tensioner. I have seen a car run with a bad tensioner and it never jumped time but the belt was flapping around every time it fired. If your getting good compression numbers I would say you don't have bent valves.

I disagree, I think its internal if its blowing air out, especially that much, Can you post a video so we can hear it?

 

[Bud92gsx]

If the valves were contacting/have contacted the pistons,Wouldnt his compression numbers be wrong..

I had bent valves this summer all 8 intake and it was blowing smoke back into the filter pipe.I had 0 compression btw.

 

[okcummins]

It's real easy to check for contact. Pull the plugs and bar it over. If it spins over nice and smooth its not hitting. Their is no reason to debate over it, I'm just trying to make sure he checks the basics before pulling the head off for nothing.

Exactly. The way the valves are angled it doesn't take much to bend them. If there bent you won't those kind of compression numbers.

 

[Breezio69]

Ok, well ill admit i jumped the gun and said "the only thing it could be is valves."

But, it is either something valve related or timing related. Maybe the belt jumped a tooth or two, just enough for the valves to tap dance on the piston without damaging the valve, and causing it not to close before it shoves air out of the intake valve.

I did say to triple check timing, then do a leak down

 

[pacn91]

ignition timing? i would think that if the valves were bent, it wouldnt run as good as he says it does. If the valves are indeed colliding with the piston, then there is only so much moshing that is going to take place before the valve breaks. Been there before...ouch

 

[loydracing]

Ok so I installed the reman starter I had before doing anything else. Just for the peace of mind and to give the wiring a good look over. I started it a few times and can not duplicate the problem again. I'm guessing it fixed it! The old starter was really loose internally compared to the reman one so it was definitely at the end of its life. I loaned out my leak down tester but I did just hook up the compressor with 80psi directly into each cylinder at TDC and there was very minimal leakage, mostly through the rings into the oil pan. I figured as much though with the compression numbers the way they are. It just runs and sounds to good to be that serious of a valve issue. I don't understand why it would puff back out of the intake like that it made no sense.
Oh and I did recheck the timing and it was dead on. Its all OEM timing components with less then 15k.

Thanks for the help though i appreciate it!!

 

[Darksun280]

Just saw this. Not the same car but my 89 camry with original starter would do this if i cranked it cold for more that 4 seconds. It's more like the starter tooth slips then anything. replacing the starter fixed my issue as well.