94 Pontiac TransSport won't crank fire up

Hi forum,

my problem is that my 94 Trans Sport won't fire up.
The whole story is that it broke down a while ago. It was still running in idle but didn't accelerate. (missfiring..) I had it towed and replaced the TPS and MAP sensor according to OBD readout. After that it was running fine for 2 weeks. Then it broke down again, like someone flipped the switch the engine stopped. Guess what I had it towed again. It turned out that the fuel pump went bad which explains the symptoms on the first break down.
So I replaced the fuel pump. Now it won't fire up when I crank it.

Here is what I

replaced
- new rotor and distributor cab
- new ignition wires
- new fuel pump and filter
- new spark plugs
- new ignition coil

checked
- it gets fuel, can see fuel comming out of the TBI injectors
- have a sprak
- see the valves moving so I assume the camshaft is turning
- have electrical power, cranked on bat and with jumper cables
- timing, I guess is correct, checked it with timing light while cranking
- tryed to fire it up with starting fluid :( no luck

I'am out of ideas and options any help is greatly welcome

Let me read between the lines: this is a 3.1: it was diagnosed as having a faulty fuel pump, you have had the pump changed, but it never fired up after that?...Is that correct?
If this is it, then the problem is still there....., never mind the pump....Do you have any codes now? Are you able to retreive the codes by youself using the check engine light "blinks"?

Yes it is a 94 3.1 liter engine. As you said, after I changed the pump it never fired again.
What amazes me is the fact that you can crank ist forever and it behaves like dead, no missfiring or backfireing, nothing.

The last idea I come up with that the timing cain slipped?? As I said I do see the valves moving whenever it is a kind of a limited view throug the oil filler cap.

Thank's for your reply

THe 3.1 has a chain, not a timing belt. Though I have seen chains skip a tooth or 2 even 3, this is rare...but not impossible. It happened to me with a ,68 FOrd 302...and in fact on every 302 that I came in contact with, 2 or 3 more, but this is history.....
How much mileage do you have? By the way, when the timing chain is 3 teeth off, it will crank very fast, wil not start, and compression reading will be very low.....this is easy to check, but i would think of this in last resort....
Other wise, I'd like to think of more simple things ....but tell me about the codes I have asked for..?

Sorry you are right I missed some information. Hope I get it right this time.
Milage: 165,000 miles
Codes:
when it broke down first I had code 22 and 34 that is why I replaced the TPS and MAP
on second time I got code 54 I had still a read out of codes 22 and 24 but I think that is because the OBD was not reset.

When I changed the fuel pump the battery was disconnected and the OBD did a reset. No codes since then even after "hours" of cranking.
To come back to my try with the starter fluid, isn't it odd that I can't get even a little missfire or something out of it??

As I said in my first post. When it broke down the second time it was like someone flipped a switch. The engine just stopped working. I checked all electrical wires, fuses and connectors. I have all dash light's and the oil pressure gauge shows pressure when I crank.

Thank you for your time, Hubertus

Can you positively confirm you hear the pump hum when you turn the key on? Here is the data for code 54
www.avigex.ca/xport/code54.jpg
www.avigex.ca/xport/dtc54.pdf
if you prefer you can have both .jpg or .pdf...
Notice that in ALL cases, DTC 54 does not mean faulty pump: it means no voltage to pump.

THe funny thing, I just finished an extensive job on my son's car , and when we finally came to starting the car, it would just crank and crank.......and....we finally found we had forgotten to plug the fuel pump.......so, a dead relay would do same....Yeah..the starting fluid..!?! Puzzling, indeed....I can't say we were better off with carburators, but..diagnosis was easier...even without the codes

Thank you LMP, I know about the codes, got myself a book before I turned to the forum.
Yes, I hear the pump hum and it continuous to deliver while cranking because I see fuel comming out of the injectors. BTW I changed the relay as mentioned in other threads in this forum didn't help either.
Since I did a lot of research before I posted this thread I guess I give it a last try with the compression check as you mentioned before. May be the timing cain really slipped?? As I said I'am out of ideas.

The compression test is logical at this point, even if it ends up indicating that something else must be searched for: eliminating possibilities is progress...
The pages about dtc54 will be there for others, anyway.

Having a '94 3.1 myself, you've peeked my interest.

Assuming your right about fuel, compression and spark I would check that the EGR valve isn't stuck open.

I had a sticky one and manage to have it stick open after a vacuum test. No way was it going to start and like you it was like a switch turned off. I knew I had fuel, spark and compression. Took me about 15 min. of puzzling to figure that one out. To close it I applied a very gentle, low psi (2 psi) blast from an air hose and I heard it pop closed. You can feel the diaphrams position with a fingertip. Started right up after that. Poor off idle performance when at normal operation temperature also a symptom of bad EGR.

On an L4 with no start, again with good fuel,compression and spark it was the spark plugs. They had all fouled out. Insulators looked black and wet, but had a nice spark between the electrodes. but under compression they weren't up to the job. New plugs and she fired right up.

If its not that, start diagnosis from scratch.

Thank you LMP and thank you NiteOwl for your reply.
I'am a kind of busy but I will do a compression test and give the EGR valve a shot.
I'll let you know about the result.
Hubertus

OK, here are my findings about the EGR valve and the compression test.

ERG, I didn't remove it but I checked it with a vacuum tool. It moves back and forth just fine. So I don't know if that is good or bad.

Compression test, the cylinders habe between 90 and 125 PSI mostly around 110. My book says 100 is minimum. Again, don't know if that is good or bad.

Checked the spark again and looked at the spark plugs they are new anyway so nothing suspicious to me.

Why can't I fire it up???????????????????????????

?!? I thought I had posted this....

These numbers (for compression) do not tell a bad story...
I read about bad ground with similar symptoms...see that:

http://www.automotiveforums.com/vbulletin/showthread.php?t=337731

I find this strange......anyway

Well it is not an electrical problem. I got a tip from a tech guy that the katalytic device may be clogged.
So I removed the O2 sensor in order to give the engine a way to breath and when cranking I hear a much better noise, something is going on, but it won't fire up. I keep trying and let you know.

Clogged catalytic will never stop the engine from firing up...it would just be powerless once running.

May be pay attention to this thread:there seems to be a pattern here!
http://www.automotiveforums.com/vbulletin/showthread.php?t=341709

Well, I guess you are right about the clogged catalytic device it was just something I tried because I'am out of ideas. Thanks for the hint to that other thread but it is not an electrical problem everything works fine.
I replaced the spark plugs again with new ones and what I hear when I crank is like the engine is almost about to fire up but then I get a real strong gasoline smell. That makes me think the engine is flooding. Could there be a problem with the ECM? Fuel is delivered to the TBI and it is injected all the time while cranking but maybe it is to much?

You will have to be careful here: if large amounts of unburned fuel have invaded the cylinders, some/a lot of it may have seeped to the oil pan and this is a severe problem: remove the dipstick and check for any gazoline smell or unusually high oil level. I've seen it before and I would not have liked to start the engine with THAT as a lubricant.

ALl of this makes me feel that your first idea about a slipped timing chain might have been the right one from the start: since this is a mechanical distributor, even with a slip that would not reduce compression a lot, the timing of the firing too would be off (lagging) and could prevent firing up the engine. That all sounds very plausible.
At this point, I'd simply try to crank the distributor "forward" to see what happens........If it succeeds firing up then it would confirm the chain problem......but check the oil first!

Try cleening all connectors. The two big ones left, the one on the bobine (=distributor). And the one at the MAF.

Hi again forum.
I'm sorry for playing dead quite some time but I was working on the car and finally found out what the problem is. In order to close this thread I think I have to let you know.

To make it short, the timing chaine had slipped! I don't know how mutch but by settig the ignition to 40° to 50° advance the car finally fired up with no problem at all. As soon as you bring the ignition timing back to normal the car playes dead as discribed im numerous posts.

I figured it is not worth puttig any further effort into this project and trashed it. :(

Thank's for all the help LMP :) and others, Hubertus