Dixond

iTrader: (1)

A couple days back, my car decided to not start. Nothing unusual had happened prior to this. No work has been done on it recently. The next day, I went out and tried again and it started up as if nothing were wrong. I drove to autozone and picked up some TL-3 Fuel Injector Cleaner. The sound that the car had made the previous night sounded like it normally would when cranking, but it just wouldn't actually start up. The starter sounded as if it was doing it's job. All of the electronic components of the interior worked normally, so I figured it was something dealing with the fuel system since it only sounded as if it wasn't being combusted. I bought the injector cleaner in case the injectors were a little corroded, as I don't know when the last time they were changed.... 2 days later after a running the car w/ 2 jitters on the freeway and one failure to start (but the second attempt 30 seconds later was a success), I didn't quite know what was going on.
Today, I got in the car to run it down to the local garage for an oil change and she didn't start up. So I waited.... And she still didn't start. After trying about every 20-30 minutes for the past few hours, I'm "bumfuzzled". The "Check Engine" light and the "Battery" light are on, when the key is in the on position. I believe the battery is fine b/c I can definately hear it pumping the pistons, but it doesn't fire up.
My only guess now is that it's
A. spark plugs (haven't been changed for a while)
B. Injectors (slowly being ruled out)
C. Computer system backhanding my fuel system

I'm not quite sure how much more descriptive I can be. I read in one of the searches to check the intake lines for cracks... or something line that, however, I don't quite know which the intake lines are or what they look like.

Any help?
Dix

SPORTcoupe

iTrader: (2)

Hmmmm......if the engine cranks over fine, it's either fuel or spark that's missing.

I don't think the ECU would be doing something like this but if you want to be sure, disconnect the negative battery terminal for about 5 minutes and re-attach it.
The ECU resets when unpowered.

Your intake piping is the stuff that comes to the throttle body from the airbox.
If you're looking at your engine bay from the front of the car, there's a big black box on the very left closest to you.
The air filter is inside this box.
Out of this box there is some rubber/plastic tubing going to the engine.
Check all this tubing for any cracks, leaks, or faulty clamps.

After that I'm pretty sure you're gonna have to have a mechanic look at it.

Dixond

iTrader: (1)

Ran a diagnostic through the OBD1 plug....
93 SC400 220,xxx miles....
before the diagnostic was run, thought it was a bad fuel pump... replaced that to the tune of $300.
Supposedly, i need to check the connections down there by the sensor and also by the ignition coil to make sure contact is being made.
Comments?

EUROJulian

Stop guessing game. When it wont start, FIND OUT what is missing, spark or fuel, or both. Go from there...

Dixond

iTrader: (1)

apparently "spark" is missing, but as i am still unskilled as to how to go about fixing this i'm looking for some feedback on how to do so.
Do i need to replace the ignition coils, or where are the wires that i should check to make sure they're all connected

Dixond

iTrader: (1)

I'm updating this thread so that CL will have a posted answer to my problem in case any one else experiences the same things.

I took it down to the local shop and had them scan the car's system w/ the OBD1 Reader. It said that there was no RPM signal received from the Crank Angle Sensor. The computer wasn't able to complete it's diagnostic check before sending a signal to the spark plugs to fire b/c the Crank Angle Sensor wasn't reading any movement.
The Crank Angle Sensor (CAS or Crank Position Sensor) is located right underneath and behind the lowest pulley on the engine. You have to go from the bottom to get to it, so removing the skid plate is a must.
I jacked up the car and took off the skid plate and took the CAS out. It is a tiny piece that is held in by one small screw. It has a wire with a plug going into it. You'll have to reach behind two other lines that will be in your way in order to get it out (I would have pics but i don't have a digital camera).
Once you have the CAS out, you'll need to verify that that is your problem by using a Voltmeter. I'm not sure of the correct "range" but I believe my car was supposed to read around 13.4 ohms according to the ALLDATA program that the shop has to keep everything on file. My CAS was never a constant number, it was always rising and wouldn't stop (basically, the Voltmeter couldn't determine the correct number). So my mechanic friend put in an order for a new CAS (I paid $112 for it, new).

When it got in, we checked it w/ the Voltmeter, and this is where we found that it should be around 13.4. I put it in, plugged it up, put the skid plate back on and turned the key... Wah-lah it cranked.
But I wasn't done yet. I figured that since the car was up for two weeks w/o actually firing after having fuel injected into the cylinders and not being ejected, it was going to be pretty dirty. I decided to change the spark plugs. I couldn't justify spending $104 on denso iridium spark plugs since I'm on a somewhat restrictive budget and saving up for some other goodies so I got the denso dual platinum. Removing the intake line isn't too bad. BUT don't brake the small line that comes off of the vacuum hose. I did and I tried super-gluing it back. No Dice. It broke off again when trying to put the tube back on. I had to play w/ it a little bit, but it'll work for now. That good thing is that it'll crank w/o that line being attached (although I'm not sure how good it is for it to be like that).

Also while I was there, and since I had the Air Box out, I drilled 4 holes in my Air Box (I think they're about 1 1/2 inches in Diameter since that was the largest bit he had). So 4 smaller ones will have to do.
BFI in the making, and yes, I can hear the difference.
I have a K&N on order from Autozone and it'll be here in 2 days.
I finally had my car home .

Next starting problem began when I brought the car home from the shop that day and decided to take it back out for an oil change and some Slick50. Put the key in, turned it, nothing. No lights, nothing. The steering wheel lock did disengage though, but no electronics turned out. Check the fuses. They were all fine except they were oddly very hot. After giving the under-hood driver-side fuse box time to cool off, I put the key in, turned it, and it cranked right up. So, I drove down to one of the local shops again and right as I was pulling into the parking lot, my A/C started flipping out and shooting cold air on full blast (even though AUTO was set and it was around the set temp in the cabin). I looked at the dash and the lights started flickering even my ABS and TRAC light were flashing on and off. So, I threw the car in neutral and pulled the key out as I rolled up to the garage. Got out, started talking to the guys and we rolled it into the garage for the oil change. Talking to one of the guys that works there, I found out that his car had the same problem when he installed a decent sized amp in his car. So after cleaning all of the battery mounts and nothing still working, I pulled the fuse out of my amp power line. I figured that a 280 watt amp wouldn't be that detrimental to my battery but, hey, who knew. The car cranked right up. Drove over to Auto Zone. Bought a Duralast Gold 640 Cold Cranking Amps (only 10 less than the Yellow Top Optima) and I plugged my fuse back in. As I drove back I had no problems with my car.
With a new CAS (although that doesn't do much, except green light the spark), new plugs, BFI, K&N air filter, new Battery, and an oil change w/ Slick50, my 220,xxx mile SC4 is running better than it has in a long while.
Any questions about the Crank Angle/Position Sensor, drop me a line and I'll tell ya all I know (which isn't that much).
Peace,
Dix