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-   -   at wits end. (http://forums.pelicanparts.com/showthread.php?t=97628)

todwic 02-09-2003 10:24 PM

at wits end.
 
Ok, here's the problem, my car won't start. Won't even act like it wants to start.<br>I've put in a new fuelpump/DME relay, swaped DMEs, swapped Aux air valves, cleaned the connections on the DME, tried several different locations for the grounds. checked my coil, AFM, TPS, Temp II, Temp I, Searched the wiring under dash and in engine bay, new TDC sensor, new TDC pin, glued a .8mm washer on a sensor and set the hieght of sensor bracket, checked rotor, cap and wires, and sparkplugs, fuses, wires behind the fuses, DME has power at term 6 and 35, and 6 and 16, and a couple others the manual sez test. with the ignition on, rpm sensor has 1.5 v and the TDC sensor has 1.0 volts at the connection. If I take the sensors out, hook one up and hold it mms away from a florescent light i have, the EMF pulse triggers the sensor. I can hear the fuel pump activate on one (I asssume that 's the RPM plug) so I know both sensors are good, and when I turn it over, I can sometimes hear a popping sound, like somethhing arcing over by the cruise contorll controll.
<br>I just got through taking all the intake apart and making sure there aren't any vacuum leaks, tightened every thing down. <br>This after the car started and ran before it died (I thought from a vacuum leak, but a sensor knocked my TDC pin out. All I have done since then (other than what I mentioned above) is install the A/C and Alt bracket and hook up the alt. and belt. My alt was out of harms way during the rebuild, so I really doubt that that is what's wrong.<p>Anyone have any Ideas?http://www.pelicanparts.com/support/...s/a_frusty.gif http://www.pelicanparts.com/support/...s/a_frusty.gif

AFJuvat 02-10-2003 02:28 AM

No success in starting it since the RPM pin issue?

I would start there I'm afraid. Can you verify fuel pressure and spark?

AFJuvat

Dantilla 02-10-2003 07:57 AM

Well, it's gotta be fuel or spark. Did you take an injector out and see if it is spraying fuel? Do the plugs fire? If so, my guess would be the timing is discomboberated.

todwic 02-10-2003 09:54 AM

Fuel pressure verified. Are the injector pulses initiated by the TDC sensor as well? I guess I'll go double check the timming, although I haven't changed anything since it started. If I were a tooth off, would not the DME adjust that small amount? If not, why did it fire and run for that little bit it did run?http://www.pelicanparts.com/support/...s/a_frusty.gif http://www.pelicanparts.com/support/...s/a_frusty.gif

todwic 02-10-2003 09:55 AM

I do have injector pulse, btw.

todwic 02-10-2003 12:57 PM

I made sure of the right sensor was hooked up to the right plug by using an ohm meter. With one sensor hooked up, I tried the different posts that correspond at the DME plug (Thank you, Clark!), so I'm good there. They are the same sensor, aye? Not job specific sensors? I'm pretty sure not, but I have to ask. Coil is good and gets batt. voltage at both posts with key on. My timing is dead on, I double checked. I think I'll check my alternator. That's the last thing I can think of.

Eduardo Castrejón Elbjorn 02-10-2003 01:16 PM

You are the gurus of the forum and I always ask you, but recently I experiment and solve my problems in this part of the engine, then I want to try.


I know that this is not good for electronics but is quick to know if you have or not spark.
Use the antique method of arch spark to the engine with a spark plug cable.

If the flywheel sensors are inverted you will not have spark, ( I know youa lready check it ).

When my engine donīt start and I had spark, fuel presure and pulse in the injectors.
The problem was clogged injector
I donīt believe that your injector clogged to one day to other.

If you have spark then try to insert fuel to the plenum by the body throtle.

If you donīt have spark the problem will be a bad connection,sensor,etc

todwic 02-10-2003 02:08 PM

I think I've narrowed it down. Using the ol flourescent light, I got pulses from both sensors and 16 rpms with the multigauge. So I'think I'll take the bracket back off, make sure it's alll good. I know the pin is exactly 5mm high. So I think I need to adjust the height of the bracket again, and make double sure the tension pin is still in the block.

Trevor 02-10-2003 06:49 PM

Do the rpm's register when the engine cranks, could be the sensors in the flywheel. Hope everything turns out well.

SoCal Driver 02-10-2003 07:42 PM

The replacement pin may not be massive enough to trigger the sensor. It might need to be in contact with the steel flywheel body. Replace it with one of the pins from the flywheel I brought over.

Eduardo is right about having the sensors connected to the correct cables. You should get a spark when they are correct. The fuel pump will stop if the rpms fall below 200. When you crank the car there is about a one second time out on the fuel pump to keep it running while the engine catches and runs.

Have you ohmed the two sensors out? Both should show about 1k ohms from the center pin to one of the outer pins. The other outer pin is a ground.

Have you checked for voltage at the coil and at the injectors when the key is turned on?

951carter 02-10-2003 08:07 PM

Pull out a plug and verify that it is firing.

Pull out the injector rail, with the injectors still in it. Put a 20 oz drink bottle cut in half under each one and turn the engine over. You should have fuel in each one.

These are some old school methods but they will show you whats going on and are easy to do.

It is very simple, you need fuel, spark and compression to make an engine run. And of course they all have to happen at the same time.

I have not been following your story but by you mentioning rebuild it makes me think that the car has been sitting for awhile. It is very common for the car to start and run for a minute and then the fuel pump or injectors clog. I once went through 3 new fuel pumps before I wisened up and drained the fuel from the tank =0 Let's keep that little secret just between us though, as I am still a little embarrassed by it.

todwic 02-10-2003 10:17 PM

Firstly, I verified fuel pressure, and I still have the gauge hooked up. Secondly, I verified non clogged injectors by touching them with a 9v. all were opening well. about 5 touches drained the fuel pressure. My problem was spark, I have found out. While I had batt. voltage at coil, I wasn't getting pulse. checked sensor resistance at every plug, check every ground I touched, checked at DME, ran the wires, zapped every device, sensor, and doohickey with ohms volts and poop. I'm running out of things to pee on. It's like the sensors just wasn't getting the right stuff. I decided to pull the bracket, and this is what I found, and what I think may be my problem.<p>http://forums.pelicanparts.com/uploads/senstool.jpg Let's say this first, I finally wised up and customized a tool for those $%&&$%^ hexheads on the bell housing holding my sensor bracket.<p>http://forums.pelicanparts.com/uploads/both.jpg http://forums.pelicanparts.com/uploads/holes.jpg <p>See how one of those holes is a little more oval, mayhaps a tad bigger than the other one?

todwic 02-10-2003 10:22 PM

The bigger one is the one I had on, the smaller one is one I got from J.Y. with my last group of sensors. <p>http://forums.pelicanparts.com/uploads/cast.jpg http://forums.pelicanparts.com/uploads/cast1.jpg <p>The cast #'s are different, too, mayhaps the molds were just a tad different, or maybe the older one's hole just got wore a little bigger? who knows, and I know it doesn't look like much, but when the sensors have to be .8mm away from flywheel teeth and a pin that's 5mm +/- .02 mm, that smidgen of oval could be enough to piss on my wheels of progress!? Whatya think?

SoCal Driver 02-10-2003 11:01 PM

Nope!

SoCal Driver 02-10-2003 11:04 PM

I'll call you tomorrow. I can get it started!

todwic 02-10-2003 11:08 PM

Quote:

Originally posted by SoCal Driver
I'll call you tomorrow. I can get it started!
my hero! I'll pm you my home # in case you don't have it
.

todwic 02-10-2003 11:33 PM

Well, I don't guess I will pm you, or email you. I trust you have my # in your cell memory.

todwic 02-11-2003 01:28 AM

Wahoo! I changed brackets, set the height, which was too low and heard the harmonic cacaphony of sensor agin starter wheel. backed it off just a hair. While she didn't start, I did get an ignition pulse. Batt. too low now, and it's only ripping by at 80 RPMs. Needs 200 to start, I think. I'll swap batt. in the morn and see what the heck.

profssr2017 02-11-2003 09:28 AM

Congrats on your diagnosis - hope we hear today that it is running!

todwic 02-11-2003 04:20 PM

OMG. I am soooooo stupid!<br>"How stupid are you???" asked the crowd.<br>"I got a pretty good Idea how stupid he is.", adds Roger.<br>"Oi vey!", chimes in Juvey and SoCal in unison.<br>I hope you understand how hesitant I am to let you in on my dirty little secret, but I have found the problem, so in the interrest of science and to prevent anyone from making the same mistake (if possible *), I will almost freely admit that I had the reference pin in the wrong hole. YES THE WRONG HOLE! I hate talking over sniggering. So I will go out and move the pin over about &frac34;&quot and start my car. Refer to signature. ***


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