MarcR94v6

....at least I think. After putting the car together after a head gasket swap, it started fine for a few days, then it took more and more cranks to start it. Not slow cranks, just took several times. And it's gotten worse and worse til now, if it sits overnight it'll take 4-5 tries to start. Sometimes if you try to get it to start on the first crank, it'll almost start, but have trouble idling and not quite get there, one time I even saw smoke from the engine bay after this. I'm thinking it must be something I did during the head gasket swap. I'd like to say that it started to start poorly a little bit before the head gasket problems but I just can't be sure.

So I took it to a shop after I check everything I could (fuel, ignition, etc), they had it for 2 days and said I did everything really well, and they couldn't find anything wrong except when sitting for a while, the battery drops to 8.6 volts when cranking, though specs seem normal once started and with engine off. They suggested I could try a new battery to see if that does it, but they weren't sure if that would fix it. So I gave it a shot, got a new optima red top and it didn't fix it, it was exactly the same after sitting for more than an hour. It runs fine once started and the gauge in the car is only slightly above the half way mark, but as we know that gauge isn't accurate, alternator is charging fine. BTW, when I was putting the car back together I noticed that they never bolted in the pcm ground wire to the block so I went ahead and screwed it in.......it almost seems like it started better without it.

A little background info: engine rebuilt 12k miles ago. During head gasket swap did new plugs, wires, intake and exhaust valves, msd coil, lt4 km. Not long before that I replaced the fuel pump, fuel filter, fuel pressure regulator, egr valve, ac delco opti. No surprise all of that checked out.

So what's my next step? Should I take it to a shop that specializes in electronics so they could sniff it out? I suppose when I save some more money I can try just throwing a new starter and alt on there to see what it does. BTW, it looks as though I can't remove the starter without cutting the y-pipe off (again) since my exhaust system is welded the whole way except for where it bolts to the headers.

Guest47904

It's easy to see if you have a power issue related to starting or charging. first with everything turned off the battery should have 12.6 volts. While cranking the starter, the battery should never drop below 11 volts (obviously checking with someone's help). Once the engine is running, it should be at least 14 volts across the battery. Anything different and it has to be investigated.

Now if you have a load that is drawing the battery down when the engine is off, that is easy to find too. Start with the fewest wires at one of the battery terminals. Usually the negative cable. Remove it and put a VOM set for the highest current reading it has. Usually 10 amps. Put the meter in line between the disconnected cable the battery terminal it was removed from. The meter should read so low that you have to change scales to read it since it says 0 right at the moment. If it reads anything at the 10 amp scale above .02 amps, you have a draw that is draining the battery while it is not running.

If you change the scale to a lower one, and you never read over .02 amps, your problem is not in the battery or charging circuit. At that point you should remove the starter and have it tested for high current draw by a reputable person. Not AZ or Advance.

If it turns out you have a high current draw, first suspect anything that was added and wired directly to the battery. Remove it and check to see if current has gone down to normal. Then continue to remove and replace fuses one at a time until you find the one that brings current down to normal.

I now have to caution you about the use of Am-meters. All meters that measure current must have a fuse to protect them from over current and burning up the meter. Every time I grab a meter that someone else has used, the amp fuse in the meter is blown. If you are using a meter to measure current and the fuse is blown. It will show no current when there may actually be current when the circuit is connected like it should be.

So what I'm getting at is if you are looking for little to no current to be there and the fuse is blown, you will see no current. Then you think there is no problem and continue looking for something else when you missed the problem entirely. So check the fuse first.

MarcR94v6

Thanks I'll look into that this week. I also removed my ac firewall box and put a cover, I kept the vacuum line, but is there any ground there that I may have missed or cut thinking it was a regular wire?

MarcR94v6

when it nearly starts, but dies on the first crank after sitting, I see smoke sometimes....This time IO ran out and looked and it seemed to be originating from around the air filter area....I jack the car up and look under there, ground seems okay, but what is this box to the left of the air filter with wires going to it? I think the smoke may be coming from there.

MarcR94v6

I think it's the cruise control module....could this possibly affect starting and can I just take it out.

Edit - It's the air filter.....the air filter itself is smoking!!! what could this mean?

97WS6SCharged

Sounds like the rocker arms a set a little bit too tight and it's back firing through the intake.

Guest47904

The smoke from the intake can be completely normal in an engine that does not fire up. Move on to testing.

MarcR94v6

Well, sitting overnight, putting a volt meter on the battery it's 12.6 volts. Doesn't appear voltage related now, it goes down when cranking but not very low, not 8.6 as reported by the shop, but that was with the old battery.

I am at my wit's end here, I'll have to take it to my engine builders who are more expensive than the shop I more recently took it to, but it must be done. I'll have to wait a few paychecks though, as I cannot afford it right now. So here's to hoping it doesn't not start at all until then. Thanks for the help.....I think I'm done for now. Just when you think you've come really far and learned a lot....you don't know jack.

MarcR94v6

here's some video of it almost starting, then starting

http://smg.photobucket.com/albums/v1...t=9-08_002.flv

http://smg.photobucket.com/albums/v1...t=9-08_003.flv

Guest47904

Do you have any fuel pressure? It seems from the video that your fuel pump is off. Also, try squirting fuel into the intake while someone cranks it over.

Your starter is cranking plenty fast enough. Cranking is not an issue.

MarcR94v6

fuel pressure has always been good, testing under several conditions with a gauge (hot, cold, sitting long) - always within spec with no bleed off. I would think the same thing, but my gauge says different.

Guest47904

So have you tried squirting fuel in the intake while cranking it over?

Or how about checking a plug or 2 for spark?

johnnyb

I dont know what the cluster lights look like on a z, but it looks like your ses light might be on? First thing is to get that scanned (even if the light isnt on actually). Did the opti get wet at all when you did the head gasket? Have you checked the lash on your rockers? Make sure the ground strap + the 2 ground wires are all hooked up on the icm as well. While your at it, make sure the opti harness looks ok and has a good connection. Have you checked the fuel pressure since you did the head gasket swap? (i know you said you checked it but didnt clarify when)

MarcR94v6

It does says "Check Gauges", but that usually doesn't mean anything unless the "service engine soon" light is also on, or oil pressure or voltage is low, etc. I am getting no codes from my scanner, it gives me a lot of operational data, but I have nothing to compare it to (ie: left injector pulse, maf x grams/second).

Rockers were done with engine running, had some trouble at first, but it's pretty smooth now, tightened them til no clicking then added 1/2 turn of preload.

I checked the fuel pressure about 3 times, the shop check it and the spark a few times themselves, but I may take it to another shop. It is always within spec whether it's sat overnight or not, no bleed off either. I even manually checked it for leaky injectors by popping the rail off and priming it in case it was flooding the intake for fuel - nope.

As far as I know, opti did not get wet during gasket swap, I drained the water from the radiator and then from the block drain plugs, it never came close to the opti, even when taking heads off with residual water. Grounds are good, I even found the pcm ground unbolted during my head gasket swap, which I put in the appropriate place block, before sanding the area to metal for proper ground. Wait, does that count as the second ground?

I checked the harness, it looks as though there is a bit of of faint redness in the metal part (corrosion?). So I just ordered a new one just now from EFI connection. I hope that helps. I just don't understand why it started fine for the first few days, then this. I was actually experiencing some problems just before this happened, not nearly as bad. I replaced a faulty EGR valve (got a code) and a faulty FPR (no code) and it started slightly better but then I started getting white smoke all the time and did head gaskets.

Also, I made my own plug wires (MSD)....do you think maybe a few of them didn't get crimped well? I've done a set before and they turned out fine, I even tested each wire with a tester and they're good.

johnnyb

corrosion is never any good especially on the opti harness. i would also double and triple check your plug wires to make sure they are all snapped on and that a wire isn't crossed. a crossed wire happens alot more than most would imagine.