Sons 300m and I need help please!

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swies

swies

Wish I had more time.
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I know this is not an A body first of all.
I have checked the 300m forums and I do not trust them like I trust you guys.

On to the problem.
My 16 year old son has a 2001 Chrysler 300M.
Saturday night when he got off work, he was accelerating onto the freeway and the car died.
He called and I went to check on him.

1. No codes. (Used my Bosch Scanner with '0' codes found.
2. Battery was low from him trying to start so we jumped it with my Denali (120amp alt) with no change. Motor tries for 2-3 cylinders then hard cranks for 2-3 cylinders and repeats.
3. Loaded it on the trailer and got it home to the garage.
4. Tested battery and it had 2 dead cells. (Load tested @ 7.5vdc after full charge)
5. Pulled starter and had it tested at the local shop. It passed with flying colors.
6. Pulled plugs, they were soaked with fuel but clean. We left them out so the cylinders and they could dry out.
7. Checked for spark on all plugs. Gapped at the spec .050 they were all nice white hot.
8. Put plugs back in and tried, no luck.
9. I pulled top 3 bolts of timing cover that I could reach and did see the belt was in place and was tight but could not see more without more tear down.

And then it was 8pm and I had to get into the shower and bed for the 4:30 am start of today.
So,
Trying to do some research and I see the following.

The 2001 3.5L is an interference motor.
I do not hear any valves clanging or banging at this point.
It only has 1 Crank Sensor and 1 Cam Sensor (on the so 1 cam could be out 1-2 teeth and it would not throw a 'Cam / Crank Sync' code, AND 1-2 teeth would not cause valve / piston clash.

Can I check valve timing without the front of the motor tear down to get to the timing belt?
Does my thought process seem logical? Like I said at the beginning, I trust you FABOS.
Where would you go next?
Poor kid is freaking out about his first car being dead.
 
so we have air, fuel, and spark on all 6? i had a 3.5 in a concorde, and it lasted through 200,000 and sold it to a kid at work. Still going strong...
that should have an IAC, MAP, and TPS. any of which could be sending a BS signal to the computer. Have we tried to slightly crack the TB by hand and see if it responds to some air at startup?

being an interference motor...i think he'd of heard some carnage instead of it just dying quietly.
 
Does it even try to fire? With a poor battery codes may have been lost. Have you installed a fresh battery and tried to start it?
 
johnnymac2k6 said:
so we have air, fuel, and spark on all 6? i had a 3.5 in a concorde, and it lasted through 200,000 and sold it to a kid at work. Still going strong...
that should have an IAC, MAP, and TPS. any of which could be sending a BS signal to the computer. Have we tried to slightly crack the TB by hand and see if it responds to some air at startup? Yes we have, no change.
I would think if any of the sensors are gunny sack, IAC, MAP, TPS, etc, I would be getting some code somewhere.

being an interference motor...i think he'd of heard some carnage instead of it just dying quietly.
Click to expand...
The only thing I can think of here is that the cam that does not have the cam sensor is off by 1 or 2 teeth. From what I have read, that could happen without interference.
 
Timing belt! I have done many. The belt looses teeth and jumps time. If it is the belt, you should do a water pump also. I can also help with short cuts if you are going to do the job yourself.
 
dano said:
Does it even try to fire? With a poor battery codes may have been lost. Have you installed a fresh battery and tried to start it?
Click to expand...
Yes, We bought and installed a brand new battery. Load test was 11.5vdc. Still had the 2-3 cylinders trying to start and 2-3 cylinders that were hard crank.
 
69MOPE said:
Timing belt! I have done many. The belt looses teeth and jumps time. If it is the belt, you should do a water pump also. I can also help with short cuts if you are going to do the job yourself.
Click to expand...

That would be my guess.

And he was:

accelerating onto the freeway and the car died.
Click to expand...

Probably a little too hard.
 
69MOPE said:
Timing belt! I have done many. The belt looses teeth and jumps time. If it is the belt, you should do a water pump also. I can also help with short cuts if you are going to do the job yourself.
Click to expand...
69MOPE Once again (you made my 8.25 3.55 SG swap happen) you are here to the rescue. I have done the timing belt on another 3.5 (2000 Intrepid) so I am familiar with the swap. In that case, it was a preventative change. In this case, my biggest question is, Can the slave cam (the one without the cam sensor) be off my a tooth or two without valve clash? No one seems to know for sure. All info just says that in '99 when Dodge went with the all aluminum 3.5 it became an interference motor. But my math / logic skills tell me 1-2 teeth should be only 12-24 degrees and that the valves COULD still be fine. As I said in the OP, there is no bad bangs or clangs when cranking and my son told me he did not hear anything when it died.
 
swies said:
Maybe, he is a teenager with a MOPAR. It is probably beyond his control. Just Genetics.
Click to expand...

Not necessarily a teenage thing, if the motor has any miles on it, any normal hard acceleration to get up to speed could make it jump a tooth or three.

It could happen to anyone.

Those are a maintenance item.
 
Sure your sensors are O.K?
 
JTG said:
Sure your sensors are O.K?
Click to expand...
I believe they are. I will ohm / volt check the crank and cam sensor today after work but if one or both had failed, wouldn't it throw a code?
 
Bad Sport said:
How many miles on it?
Click to expand...
120k. PO showed us / gave us docs where he had it done at 80k so I thought we were safe.
I guess he could have put in some cheap Chino belt in...
Without other great wisdom coming down the pike, I guess I will head home after work and start pulling the front of the motor apart.
Wish there was some way to check the cam timing without tearing it apart.
Inspection ports or some such thing...5 hours of work just to find out there is no problem and they are good doesn't sound fun after a full day of work..
Let's see, Alarm went off at 0430...commute...work @ 0600...off work at 1500...home @ 1600...into the garage...out 5 hours later=2100 if I skip dinner. UGH:wack:
:banghead:
 
40K on a new belt "should" be good, but you never know.

My buddy runs a top notch repair shop and he recommends 60K for replacement. Although, I have not done it and got by, lol.
 
Very similar thing happened to me. I accelerate a little harder than normal onto a highway and it just flat out died. It had about 145,000 on the clock. 03 300m. Turned out to be a fuel pump. Without fear of issues with interference at the valves you could:
- have someone crank the motor over inside and spray some gumout into the unhooked intake tube from the filter box
- if you have a gauge set up you can get to the fuel rail test port on the drivers side (bastard to get to down inside the intake runners) and test for fuel.
- unhook the rail at the fuel inlet side and get a basin to see if you have fuel

I know you said the plugs were soaked, but that doesn't necessarily mean you've got fuel.... I thought I had a real problem when mine died, but a quick check with a can of gumout proved the fuel pump was shot.
 
if it's timed correctly try a compression test
 
roughidle said:
Very similar thing happened to me. I accelerate a little harder than normal onto a highway and it just flat out died. It had about 145,000 on the clock. 03 300m. Turned out to be a fuel pump. Without fear of issues with interference at the valves you could:
- have someone crank the motor over inside and spray some gumout into the unhooked intake tube from the filter box
- if you have a gauge set up you can get to the fuel rail test port on the drivers side (bastard to get to down inside the intake runners) and test for fuel.
- unhook the rail at the fuel inlet side and get a basin to see if you have fuel

I know you said the plugs were soaked, but that doesn't necessarily mean you've got fuel.... I thought I had a real problem when mine died, but a quick check with a can of gumout proved the fuel pump was shot.
Click to expand...
Had the same thought. Tried with starting fluid when we were dead on the side of the road and tried again after we had the wet plugs out and dried them and the cylinders. There was no change. Just for giggles I did put a pressure gauge on the rail and showed 50 psi. Test was repeated 3 times to get myself convinced.
 
3.5L is an interference engine, but I have never seen one bend valves. Why, I don't know?
 
We have a rule of thumb in the snowmobile world; a wet plug needs replacing. I realize that in the automobile world, this is overkill. And I realize that Platinum plugs ain't cheap, so perhaps a spark test might tell you something.
And, as mentioned,a compression test.
If your engine has both a crank sensor and a cam sensor,and no codes, then perhaps they've lost sync. However most ECUs only look to the cam sensor during cranking, and after that just count. It's hardly likely that a loss of cam sync would cause an engine to die,once running.But a dead spot on the TPS, hmmmmm
You don't, by any chance, have an aftermarket anti-theft device on it?
 
swies said:
120k. PO showed us / gave us docs where he had it done at 80k so I thought we were safe.
I guess he could have put in some cheap Chino belt in...
Without other great wisdom coming down the pike, I guess I will head home after work and start pulling the front of the motor apart.
Wish there was some way to check the cam timing without tearing it apart.
Inspection ports or some such thing...5 hours of work just to find out there is no problem and they are good doesn't sound fun after a full day of work..
Let's see, Alarm went off at 0430...commute...work @ 0600...off work at 1500...home @ 1600...into the garage...out 5 hours later=2100 if I skip dinner. UGH:wack:
:banghead:
Click to expand...

A receipt for a new belt does not mean the belt got replaced!
 
Tore it apart last night.
Timing Belt looks new, Water pump looks new. Entire timing belt cavity is clean, no belt dust, and no water seepage.
Worse yet, Timing was dead on.
Pulled the plugs and shoved the scope down the holes. Pistons all look good. They all move up and down like they should.
After work today I will run compression test and use the scope to look at valves.
What do I look at next?
Already checked all plugs for spark.
PCM shows no codes still.
I was sure the timing was off.
 
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