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 #379471  by Loverman
 June 22nd, 2019, 3:14 pm
This problem is my nightmare!
I did everything! And it's still there. Before engine rebuild it was running smooth! Barely You could feel idling. But now there is shaking.
What i did:
Every oring a nd gasket replaced
Checked for vaccum leaks - everything is ok
Checked spark plugs - same here
Checked engine mounts - ok
Checked and aligned sprockets (changed timming belt) with locking tool
Checked fuel injectors (replaced with base model and nithing changes) cleaned and changed orings
Coils seems to be fine
Crank and camshafts sensors seems to work fine

Only code i get is p0420 (catalic converter on the passanger side) and i didn't checked it yet.
I didn't checked exhaust manifolds for cracks.
In diagnostic program injectors timming is great and there is no differences between heads.
Power seems to be ok (I don' t have another m to compare) aswell as gas mileage.

I dont know what to do next.
Help :D
User avatar
 #379504  by hrmwrm
 June 24th, 2019, 4:33 pm
have you cleaned throttle body/idle air?
replaced spark plugs(not just checked)
ran some injector cleaner through the tank to make sure you have a clean spray pattern?
User avatar
 #379509  by ThaJuggla817
 June 24th, 2019, 7:29 pm
If you've done all that on a rebuild/overhaul and it's doing that, and all the symptoms vs the fixes performed, what's screaming at me is your fuel pump/filter(since it's a single unit).... Just my 2¢ and I could be wrong... Now, if you haven't replaced the plugs, injectors, and cleaned up the throttle body while in there, then please stop touching cars.

Now, you said something about a p0420? Did it ever occur that you may have answered your own question? Legitimately asking.
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 #379516  by ggariepy
 June 24th, 2019, 11:22 pm
A shake at idle sounds like a dead misfire on one cylinder.

Fortunately this can be easy to isolate on these cars, being that the coils can be safely disconnected while the engine is running without the chance of getting shocked.

One at a time, remove the connector from each coil in sequence. If the engine begins to run worse, plug that one in and move on to the next.

If you find one that doesn't seem to make a difference in how the car runs, you have found the dead cylinder. Now the thing to do is find out why it's dead.

Hopefully it will be poor connection between the plug and the coil, or the coil and the wiring harness, a bad coil, bad wiring to the coil (i.e. a pinched or chafed wire), a bad spark plug, etc.

If you find a dead cylinder and cannot find an ignition-related problem for it, then your next step is to look for a fuel-related problem. Is the injector firing? Is it clogged? Are there any leaks at the connection to the fuel rail? Is the injector either dribbling or gushing fuel into its port?

Finally we move to the less likely. Does that cylinder have compression? I would recommend a leak-down test if you get this far. If you find a leak then you're going to be tearing the engine down again to determine the cause.

You say you did a rebuild/overhaul on an engine that ran smoothly before you started. Why? Was it burning oil excessively? Did the timing belt break? What caused you to tear the engine down in the first place? Did you have a professional machinist measure all of the dimensions (e.g. cylinder diameter, cylinder taper, main bearing clearance, camshaft bearing clearance, etc.)? What new parts were put into the engine? Did it get new pistons and rings? Was the engine machined to accept a larger piston size? Were the valves replaced or at least lapped? Was the valvetrain reassembled properly?
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 #379517  by ggariepy
 June 24th, 2019, 11:27 pm
One more thought for you. If it really runs roughly you might have a bad upper intake plenum gasket. This is easy to diagnose. Spray starting fluid on the running engine around the intake. If it smooths out, replace the upper intake gasket, and make sure you follow the torque sequence for the bolts. Mine has this problem right now.
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 #379519  by FIREM
 June 25th, 2019, 7:17 am
Use Caution disconnecting coils, be brief in the time left disconnected. Extended time unplugged could damage the drivers in the ECM.
Use EXTREME caution checking for vacuum leaks. Starting Fluid id extremely flammable.
A few basic checks should be done before throwing parts at it.
Compression Test to see if all cylinders are within 10% of each other.
Fuel Pressure Test : Should be 58 +_ 5 psi at all times.
Tools for both usually can be rented for local auto parts stores.
User avatar
 #379522  by Loverman
 June 25th, 2019, 12:08 pm
hrmwrm wrote: June 24th, 2019, 4:33 pm have you cleaned throttle body/idle air?
replaced spark plugs(not just checked)
ran some injector cleaner through the tank to make sure you have a clean spray pattern?
I clean tb and iac every oil change. Spark plugs, in my country, cost something about 300 PLN (iridium ngk) it's very expensive for spark plugs. I will buy new ones in next week. I used injector cleaner.
Rebuild was done because main bearings were worn. I checked for vacuum leaks (as I mentioned above). I did changed upper gasket.
This shaking is not similar to shooted coil (i know that shaking). This is something like engine mount but smoother.
Injectors were cleaned by specialist. I even changed fuel rail to injectiors.
Engine rebuild was done by mechanic who (supposedly) know this engines very well (now i doubt it). I wanted to rebuild it but at the time didin't have a space.
Yes i have p0420 (catalic converter ) and i thought that problem was in injectors (leaking on passanger side) but in diagnostic program timming on each head is the same.

for the records. In Poland we can't rent tools that easy :) But fortunately i have this tools (in workshop where i'm working) but i dont have time to check everything. Tomorrow i want to check that catalic converter. Next i want to check fuel pressure.

About spark plugs... now i'm running on iridium champions