low vacuum, hard start after hd gasket replacement

[hondoland]

Hi! Our customer brought in a stock '02 PT Cruiser w/116k miles - "overheats". Determined that it had a blown head gasket and replaced the headgasket, water pump, timing belt, and O2 sensor (possible contamination). Sent the head to a machine shop for checking, no problems, but they advised doing a valve job. After filling the combustion chambers with gasoline, a couple of the cylinders had lost a small amount of gasoline in about 15 minutes, so we declined the valve job, (customer's money). After reassembly, we had extremely long crank/start time and low vacuum, lousy idle. Immediately figured timing marks were not set correctly. Blamed it on "crank pointer to trailing edge of tooth" and "exhaust cam mark off/below intake cam mark by 1/2 tooth", setting procedure, so anyone can make a mistake, right? Well, we have reset and rechecked the timing marks, again and again, and we still have a vehicle that doesn't run properly.

Symptoms: 1.) Hard start, long crank time, have to add accelerator to start and lower to idle.
2.) Rough, erratic idle, may die at times while idling.
3.) Low vacuum, 11" to 13", after cold start vacuum may be at 14", and runs/idles best ever since repair, but the vacuum eventually falls, and if under 11", engine dies.
4.) Long term adaptive fuel eventually goes to -24.8, (after going into closed-loop), coinciding with the falling vacuum readings.
5.) Short term adaptive fuel still trying to lean system.
6.) Fuel pressure 58 psi.
7.) O2 sensor switches rich/lean but eventually sets dtc P0127.
8.) All other sensor readings/responses seem normal or at least in line with how the engine is or is not performing.
Experience is telling us that the problem is in the timing, but for the life of us, we can't find fault with how we aligned the timing marks. We have even experimented with a tooth this or that way.

We could use some guidance or direction. Ask questions, if we have not provided enough information.

Thanks

[Cal Cruzer]

P0127 is Intake Air Temp Too High.
Maybe a faulty IAT sensor? Lots of people have broken those little things accidently.

Not sure if that would cause all the problems you are describing

It that the only code?

[Cartman]

just to verify, you set the crank sprocket so that the arrows line up, then you aligned the camshaft sprockets having both sprockets pointing straight up with the exhaust sprocket set a half tooth down from the intake? did you install a new tensioner? if all that was followed you shouldnt have a timing issue. have you gone through and verified that all gaskets are still in place and that all vacuum hoses are connected? check to make sure that you havent accidentally broken any wires or sensors. have you run any compression checks after the repair?

[hondoland]

Thank you for the responses.

I am sorry, but that was a typo, the only code we get is P0172. We have this feeling that the problem concerns timing, because we are only 98.6% positive that the timing marks are lined up properly. This is due to different opinions, based on line of sight, about crank pointer pointing to the "trailing" edge of the crank gear tooth, and the "1/2 tooth apart" cam gears requirement, when the cam gear markings are not centered on a peak or valley of the gear teeth. We even looked at the pictures for reference. With all this and after trying variations of these settings, we still have a car that doesn't run right.

All wiring and vacuum hoses were checked and appear to be in good condition. All other sensors are responding as expected.

[slartyblarfast]

Sounds like a possible clogged cat....Also are you sure you cut the cam gears on correctly? They can be installed 2 different ways..... I think one side says something about use for 2.0 engine but not sure right off the top of my head.......