Problems after installinf new head.

[progman]

I have been trying to trouble shoot a problem I'm having for a few weeks now. I put a new head on my CA basically. I installed a new water pump, new gaskets and head studs. I put a new timing belt on as well.

I start my motor up and it idles around 500rpm. it does not like to rev up from there. It's running rich and the vacuum is only at -10psi it was at least double that before. If i disconnect my boost gauge and create a leak the car sounds better and idles at 800rpm.

I checked my MAF, timing, tps, fuel pressure (36psi static), compression and I checked for other leaks.

I was thinking maybe i plugged my injectors in out of order?? what would happen if I did do this? I was beeping those wires out two nights ago but I had to leave before I was finished. So I'm going to make sure this is correct next time I work on it.

Also I was reading about people setting there timing off my one tooth on the exhaust or intake cam. So I was wondering if this was it. I'll check my timing belt next time I go down. Whats the beat way to make sure this is correct? re-install the belt? turn it until the marks line up again??

My ECU in mode three beeps out the code for the knock sensor (I haven't wired it in yet). and thats all.

I'm thinking about also opening up more vacuum leaks to see if it runs any better (maybe i'm just running very rich)

My wide band doesn't go below 10:1 it will just say "rich" and thats what it is saying when I idle. But it used to do this before the new head as well.

Anything else I should check? or try?

Thanks

[ca18det240hatch]

To check your timing belt is simple, without disassembling everything. Take off your upper timing cover, its tricky to slide out, but with some manipulation and a bit of forcing itll come out.

now, once thats off, turn your motor so that you can see the second timing mark from the left on your main pulley, lining up with the timing pin. You have to be TDC on cylinder one compression stroke. If you line it up with the second mark from the left on the crank pulley and the marks on the cam gears are both facing the inside, or eachother, turn it 360 degrees so that the mark on teh crank lines up again (second from left remember) and then your marks on the cam gears should match the marks on the cover behind the cam gears.

FSM for more information.

[dattodude]

Injectors in the wrong way just mean sequential injection is not working it's best.I ran for 5000kms with my injectors wired up wrong. Still managed 175kW at the wheel. Made 5kw difference.

Rich mixture is very likely an air leak or incorrectly routed/terminated vaccuum hoses.

It could also be a misaligned TPS. So that ECU things you are in off-idle position. If you've 'straightened up' the TPS to make it look good, you've caused this problem on your own. I was guilty of this 15 years ago, and my car stalled in traffic after 30 mins of driving from overfuel. I readjusted the TPS using the workshop manual, and all was fixed.

Cheers,Chris

[progman]

Thanks for the help dattodude,

I checked all my injectors and they are now in the correct positions (if they wernt before)

I checked my tps again and it's .5volts with no throttle.

I checked my compression again and I got 150-155-150-150

Right now I'm looking for boost leaks.

If I dont find any i'm going to go through the FSM again and make sure I checked the tps correctly.

Thanks.

If anyone else has any advice I would be glad to hear it.

[progman]

To check your timing belt is simple, without disassembling everything. Take off your upper timing cover, its tricky to slide out, but with some manipulation and a bit of forcing itll come out.

now, once thats off, turn your motor so that you can see the second timing mark from the left on your main pulley, lining up with the timing pin. You have to be TDC on cylinder one compression stroke. If you line it up with the second mark from the left on the crank pulley and the marks on the cam gears are both facing the inside, or eachother, turn it 360 degrees so that the mark on teh crank lines up again (second from left remember) and then your marks on the cam gears should match the marks on the cover behind the cam gears.

FSM for more information.

Something big must be wrong then. When I installed my timing belt. I lined up all the marks and then tensioned it. (I followed the FSM) Then i took my ratchet and turned the motor over like 50 times to make sure nothing hit. the marks never lined back up again. they are always off by different amounts.

I don't understand how just putting the crank pulley to TDC on piton 1's compression stoke and then turn it over 360 degrees will make it line back up.

I'm going to check the FSM.

Thanks,

[progman]

I did this with my timing belt and the marks where no where even close ( could not see them). So i turned the crank until they got close and the intake was off my 5 teeth and the exhaust was off my 4 teeth. I'm not sure if there is anything wrong with that or not but I'm going to redo my timing belt next time I work on it. I'll re read the FSM over in case I missed something.

Also I redid my timing with the car idling at 850 and my CAS was all most advanced as far as it would go to get 15 degrease BTDC.

My car is also running extremely rich and I used my safc to lean it out and it was able to rev alot better but the vacuum was still only -10psi.

I also got rid of all my boost leaks.


Modified by progman at 10:10 PM 6/17/2007

[ca18det240hatch]

dood im not talking the marks on the BELT

im talking theres marks punched on the cam pulleys themselves.

if you look really close, youll see them, theyre dots, and then if you look at about 3:00 on either side of each cam pulley on the plate behind the pulleys, youll see match marks, just straight lines punched into the plate

your cam pulleys marks should line up with teh marks on the plate behind them when youre at the second mark from the left on your crank pulley on the compression stroke.

read the section in the fsm, itll become clearer. Its in the middle or near the end of the EM- Engine mechanical section.

[progman]

Oh, I see what you mean, that way I will be able to tell if my belt is off. I was thinking only about the belt marks.

I'll check this when I work on it tomorrow.

Thanks.

[ca18det240hatch]

yep. you dont even need to worry about those white marks on the belt if you do it this way...the white marks are useless. if your bottom one is on the second mark from the left and your top two marks on the cam gears line up with the matchmarks on the back timing cover, while its on intake stroke, youre fine.

[mikesim]

you haven't mentioned that you counted the teeth on the timing belt between the cams and between the exhaust cam and crank. even if you're all lined up, you could be off a tooth, and that's why you have low vacuum.

[ca18det240hatch]

we should be pulling about -15 or so on the gauge right? ive never actually been sure about that one.

[progman]

Well, I redid my timing belt after finding out I was off a tooth on the exhaust cam. I cranked it 20 times by hand and started it up. unfortunately there didn't seem to be much change.....

-12psi at idle. better than the -10 but not even close to what it should be.. I had -20 before.

I'm going to check the idle again and re set the timing again and see if that helps any. Also I'm going to re-burn a few EPROMs and try to get the thing to idle a little leaner. still ran rich.

I only had a minute to run the engine. but I'm still frustrated with it. Next time I go down I will update this. I didn't count the cogs. looking back at it I should have. Hell maybe I'll just re do the timing again. It only takes an hour now.

Thanks for everyones advice.

[progman]

I went to work on the car again yesterday. It was running very rich. It was idling fairly rough at 800-900RPM (no fast idle... I'm not sure why not - I will check into this next time). I set the timing to about 15 degrees BTDC. Vacuum was still terrible at about -12 PSI. I revved it a few times and it struggled at around 3000 rpm and up. If i give it gas slowly it responds better.

When I redid the timing belt I checked it three times before and after the belt was on. I had a friend check it as well. I didn't count the teeth. ECU still only shows a 34 (I can't find the plug for the knock sensor) I'll look for this next time I work on it just to get rid of any possible problems so I can beep out a 55.

Things on the list to do:

find plug/plug in knock sensorreplace dropping resisters with the DSM factory ones. (I made my own dropping resisters- but I have been using them for a year; so I don't think this will fix the problem)re-do timing for the third time and count the teeth this time as well.Burn a EPROM chip for 550cc injectors and the stock MAF and switch my z32 MAF for the stock one and see what happens.

...the vacuum problem is related to the intake/turbo piping and the valves.

are my valves ****ed?

My compression is 150psi across the board.

After I do all these things I think I'm going to pull my head. Can I reuse a cosmetic MLS head gasket?

Could anything else be wrong? could my turbo have ceased up and not spinning like it should? Any other suggestions would be great because I think I'm coming to the end of the line.

[ca18det240hatch]

you should be able to bring your timing in with the CAS and have it be roughly in the middle of the adjustment. If thats the case, youre fine.

if your top marks line up with the matchmarks and the bottom one is on the second mark from the left, youre fine.

-12 psi of vacuum is low, but almost to acceptable. Should be -14.7 or around there. You most likely have a vacuum line leaking or your intercooler piping is leaking.

also, check your TPS. if you go between two of the terminals from the tps (i forget which two, its in teh manual) you should adjust it till you get 1 ohm or close to it. mines .98, close enuff. Knock sensor shouldnt have anything to do with it, i ran mine without one for 6 months and it never even hiccupped

if youre getting 150 psi across the board, chances are that your valves are fine, as you would get lower compression if there were problems with them seating. I dont even get 150 psi with my rebuild....altho i havent checked it again yet since the last time, and even that time i was lucky enuff to have a cylinder rise from 90 psi to 140 psi in a few weeks.

if you wanna see if your turbo is spinning ok, take off your inlet tube and spin the turbine. If you can spin it by hand, and theres little to no shaft play, youre fine. I ran my car for a full day with my BB turbo siezed, and besides being slow, it ran just fine.

and i wouldnt bother pulling your head, those compression numbers are really nice. unless your blowing white sweet smelling smoke, dont bother.

[progman]

I made everyone pictures.

As you can see my CAS is pretty far to the one extreme. I checked my TPS the voltage way with the FSM today.

I get .53 volts closed and 4.1 volts open (0.5-4.0 is the correct readings)

I'm going to take off the upper cover and check the timing again the way you said to check it just to make sure it's still lined up. (I don't see how it could have changed. I'm going to take pictures of that)

The turbo does spin ok.





Do i block off that open port underneath my throttle body?

things that I noticed today:

If I pull my fuel pump fuse the car's idle smooth out real nice until it stalls from lack of fuel....

It's starting to stall now and will not start unless I release the fuel pressure. Then it starts back up and after awhile it does again.

(It wasn't doing this before)

I now seems like it just running extremely rich. I created a leak in the vacuum by unplugging my boost gauge and it ran a lot better (still ****y but better) it was idling at like 12:1 with that line taken off. with it attached it is like 10:1

but I can't rev my engine with it detached. it gets too lean.but with the line attached it just idles super rich and it like 11:1 12:1 but the car has no power at alland if i rev it up it will stall when i let off the gas half the time.

I didn't replace the dropping resisters and i will be doing this tomorrow.

here is my thought. my dropping resister may be messed up and used to make my car run rich but with my larger injectors now the problem is bigger and its running too rich now.

I don't know. I'll post updates when I replace these tomorrow.


Modified by progman at 4:42 PM 6/22/2007

[ca18det240hatch]

if youre talking about that 3/4 inch hose under your throttle body, NO!!!!!! bad doggie, you NEED to run it to your intake tract about 10" from the throttle body, thats your feed for your idle air control.

[progman]

no, that little tiny thing at the very bottom of the throttle body

[progman]

So after fixing my timing belt which was off by a tooth I decided to try and see what the stock rom tune would do on my car.

I put it in and it ran better. I set my SAFC to 2 in 7 out. and the car ran ****ty but not as bad...

So i decide to try and limp it home.

So i started driving it and watching my A/F ratio and i started tuning with my safc on the 30 minute ride home.

anyways, by the time i got home the car was running much better and i was boosting at 8psi (my max)

So the problem was just very poor tuning after I fixed the timing belt.

I'm glad to have my car back. I just need to redo some rom tunes to get this right.

I'm going to go play with my car now..

Thanks for all your help.
Modified by progman at 2:45 AM 6/23/2007

[progman]

I also replaced my dropping resisters with the DSM ones and it seamed to help. I had air core resister before and they put out lots of eddie currents (my electronics minded friend told me)

The DSM ones look so much better and no interference from them.. my safc seems to respond better than before I put the head on.