Odd starting issue

BLaCk_1cE · 07-19-2009

Ok, so heres my situation. Andrew and I just completed my head gasket install the other day, topped off fluids, and re charged my battery with my little charger. I get my car started the next day, takes a *little* bit to turn it over, but it does fire up. I realized though that I didnt put the EGR block-off plate back on so I was blowing flames out the side of the head. Put that back on, she starts right back up fine.

So then, I take it around the block a little bit and I notice that my car is intermittently losing electrical power (dash dimming, radio turning on and off, etc) and she finally does just die. I get out, check under the hood, shrug, then get back in, try it again and notice that my car is making a weird humming noise inside that seems to be corresponding to the electrical charge from my car (ex. if I hit the window button the sound changes). I check my connections, and notice that my CAS was basically just dangling there (forgot to tighten it in all the way) screw it in all the way, try to start it, nothing. I dont understand how I was able to start it in the 1st place (Could it be upside down or something?)

The car will turn and turn and turn but never just fire up now. When i open the door to my car, the humming noise comes back, the little red light that says if a door is open is dim, and my oil pressure gauge goes to 100 psi. With the key in the on position the noise is still there. The lights wont turn on, the windows wont roll down, radio doesn't come on, nothing. When i go to turn it over, the humming noise will go away for as long as I try cranking it. I dont have a battery tester, but i did try jump starting it and using my little charger. I guess what I dont understand is how it did fire up, I let it warm up for ~10 minutes (however now that i think about it, it did randomly die while warming up and re-start itself), drove a little bit, and now its just like this. I had to push it home 1/3 of a mile which sucked. I havent driven this since May, I miss it bad

I know this is alot to read, and if i remember anything else or if more detail is needed, ill chime in with it. Thanks! ps This is the 420a motor, yes its a PITA.

**asshanson** · 07-20-2009

When I was looking at the CAS, it didn't seem like you could put it in upside down or anything, no moving parts, maybe magnetic? I'd check to make sure all your other sensors are still installed. I thought we tightened the CAS, but maybe not, maybe we left a few others hanging there to be put on later.

If those are all fine, check compression, fuel, and spark. Battery shouldn't be dead if it cranks fine.

notsostockgalant · 07-20-2009

you wouldnt have accidently left the motor to body ground off?

**asshanson** · 07-20-2009

Only the head came off, didn't mess with any grounds.
I guess it's probably not a compression issue since it was running fine. Maybe check timing to verify you didn't bend valves if the belt skipped. I'm going to guess fuel pump won't turn on because of electrical issues or maybe spark.

BLaCk_1cE · 07-20-2009

I find it odd that with the key in the on position, the windows wont roll down, radio wont turn on, and my lights wont even turn on. What is the explanation for that?

BLaCk_1cE · 07-22-2009

Ok so i just had my friend w/ his brand new red top come try jumping me. We kept his battery in his car, took mine out, and hooked the jumper cables from his battery directly to my terminals. The issue still persists (humming noise, oil gauge goes to 100 psi, lights wont turn on).

What we did notice is that when I tried to turn my lights on, the tail lamp relay clicks loud. Hmmm.

So what do you guys think? ps, I hate electrical gremlins.

BLaCk_1cE · 07-30-2009

Ok, so just went and tried figuring it out, but still with no luck. I noticed that the fuel pump also doesn't even prime when switching into the "ON" position. The lights, radio, nothing work (except dim rear view mirror lamps, and my oil psi gauge with goes to past 100psi). Also, the humming noise I hear inside the cabin seems to be coming from somewhere behind the radio for more information. Could it possibly be some fuse that may have gotten f-ed? They all look good, but maybe looks are deceiving? How about the possibility of my ECU being the problem? What can we immediately eliminate as the problem? and in doing, so where will that lead me to? I checked the cables for any corrosion and they are perfect copper colored. I also just got an OBD-II tester from autozone, and when i plug it in and scan for codes, its says "please connect to vehicle", and then i turn the key to "ON", the OBD-II tester just shuts off. ps: I understand this is the 420a and not everyones exact cup o tea or most knowledgeable field compared to the 4g. Where are my 420a brethren?! pps: fml

**asshanson** · 07-30-2009

Take apart the ECU and see if it looks bad? Caps leaking or such?

mukapahnpy · 08-05-2009

^^^ I'd go with that. There's not much behind/under the radio; starter relay, ECU, heater blower?

BLaCk_1cE · 08-12-2009

Just got back from up north for about 5 days and tried this technique. I hooked the positive jumper up to the positive cable and the negative jumper up to the chassis, and nothing worked in the car. Then, I tried attaching the negative jumper to the negative cable and the problem came back. While I let the negative jumper sit attached to the chassis for a while, the power actually came on, everything worked-lights,radio, windows, etc. The only thing that didnt happen was that it didnt crank this time. So, does this mean that I need a new negative cable then? or what does that mean exactly?

**asshanson** · 08-12-2009

I just remembered you had unhooked all the battery stuff for the HG job, right? Maybe something didn't get put back on the same way? Or broke somehow?
Check to make sure you didn't forget to hook up one of the grounds or something.

BLaCk_1cE · 08-12-2009

What about the alternator, did we mess with any grounds while down in there that could affect this problem?

ESchwanz · 08-12-2009

Quote:

Originally Posted by BLaCk_1cE

What about the alternator, did we mess with any grounds while down in there that could affect this problem?

A ground may have broken & just coincidentally happened at the same time of your work. Ground the head to the body & recheck ALL ground points. Car's don't start if not grounded properly or run... needs a complete circuit.

BLaCk_1cE · 08-18-2009

Found the missing link, when we were adjusting the throttle cable, we unhooked one of the grounding points from the throttle cable area. Re-attached that, and she fired right up!

**asshanson** · 08-18-2009

Good to hear!