Question about Chrysler Concorde

2 Answers

MISFIRE ON CYLINDER 5. I have changed plugs, wires, coil pack, fuel injector, and ECU unit. I have had two compression tests and it was put on a diagnostic machine. Everyone is scratching their heads as to the cause. The vehicle is a 1997 Chrysler Concorde LXI. If this was a random misfire I might think it was timing. When on the disgnostic machine it said misfire on 5 the technician told me it was probaby the fuel injector. I replaced it. I took it back and told them that was not the problem. The checked out the car for spark, compression, and had the thing for 6 hours. The check engine light was out so they said to watch it. Several miles later, the check engine light was back on. Same code. My son took it to a mechanic down from where he works, he could find not reason for the code. He checked spark, fuel injectors and compression. He scratched his head and said I don't know. Maybe it's the ECU unit. The Ecu unit has been replaced and I don't have a misfire code yet, but the systems still read not ready. I have put over 300 miles on it since we changed out the ECU. It is still missing, because I can feel it. What can I do to get the systems readu. One page talked about driving patterns and the computer was looking for that. Do you know anything that might help me pass inspection. Two of 4 systems read not ready. Catalyst, O2 sensor, O2 sensor Htr and EGR system. I forgot to mention I also changed to O2 Sensor in Bank 1 previous to the fuel injector.

Posted by on

  • krb2460 Oct 12, 2008

    99 Chrysler Sebring. Ran fine one day and the next was sputtering and misfiring. Changed plugs, wires, cleaned injectors and they are all working correctly. Put on new fuel filter and checked fuel pump, which is also good. Put new MAP sensor. Ran diagnostic a was told it was the EGR so put in new one. Still running really bad. Could really use some new ideas.



2 Answers

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

Same problem. 94 LHS 3.5L engine. Noticeable rythmic misfire at idle. Looks like cyl 5. When I pull the injector connector off of cyl 5 the idle rythm does not change. It does if i pull the inj connector off of any other cylinder. Spark OK. Injector ok using seperate 12vdc supply (clicks). Connector to injector has pulses on it verified with a test light. Inj coil resistanceis 12 ohms, exactly what it should be.

Still need to check compression and intake manifold gasket

Posted on Apr 20, 2009

  • LHSdude Apr 24, 2009

    Just checked the compression. It was fine on all cylinders. How hard is it to change an injector? How can I prove beyond a doubt that it could be the intake gasket? I tried some carb cleaner around it but heard no change in engine pitch/rpm, etc.



  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

Same problem, after plugs, wires, coil pak, computer, fuel injector, the problem was a bad lower intake manifold gasket. Gasket was broken on the lower section in the valley between the heads so it would not show up when I used an unlit propane torch trying to locate the problem. Be very careful with the o'rings on the fuel rails, they are very hard to find.


Posted on Oct 07, 2009


1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya Mechanic can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repair professionals here in the US.
click here to Talk to a Mechanic (only for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

P0303 cylinder 3 misfire

If # 3 cylinder has spark at the plug it must fire if the following conditions apply. Injector is supplying fuel to the cylinder. and cylinder compression tests OK . So check above ,one or both must be at fault.

Jul 17, 2014 | 2003 Ford Ranger Regular Cab

2 Answers

2008 Cadillac CTS returning P0303 after replacing spark plug and coil pack

Error Code: P0303
Cylinder 3 - Misfire Detected
Possible Cause:
Wiring harness, igniter and fuel injector connectors.
Ignition system. (Spark plugs gaps)
Fuel injector No. 3.
Fuel pressure.
Running out of fuel.
EVAP canister purge valve.
Evaporative emission system.
Low compression, cylinder No.3. (check valve clearance and throttle plate for excessive wear)
Engine control module (ECM).

Feb 27, 2014 | 2008 Cadillac Cts

1 Answer

1999 mercury mystique cylinder 2 misfire ! Changed gasket, plugs, wires, and coil pack and problem still exist !!! Please help !!!

Okay kevin, the first thing is to make sure there is no vacuum leak, start the car and look and listen around for a hissing sound.if no leak is found then we will move on to the next test which would be a compression test, this test will tell you if the cylinder has compression and will help with the next step. seeing that you replaced the plugs wires and coil pack, if you have good compression then the injector would be the next step. check the connector on injector, if all looks good then the next step would be to swap injectors from that # 2 cylinder with #4 and then drive the car and if light comes back have it scanned and see if the misfire moved to cylinder #4. if it did move then you will be sure it is the injector. do compression test first , test all cylinders, make sure to have all plugs out and unplug coil pack connector when doing compression test. write me back with the results. good day

Nov 12, 2012 | Cars & Trucks

1 Answer

2003 Hyundai Sonata with 4 cyl. PO301 error code. Have replaced spark plugs, wires, coil packs, and mass air flow sensor. Replaced air filter due to heavy gas smell. Car was starting after tapping gas 3...

P0301 - Cylinder 1 Misfire Detected.

Possible Causes:
- Improper spark plug at cylinder #1
- Insufficient compression at cylinder #1
- Incorrect fuel pressure
- The injector circuit is open or shorted at cylinder #1
- Fuel injector #1 may be faulty
- Intake air leak at cylinder

Possible Solutions:
- Perform Injector Service
- Replaced Spark Plug #1
- Replaced Injector #1
- Replaced Ignition Coil #1

Being you have a heavy gas smell I would look into the injectors. If injector #1 is over producing it can cause a misfire. Test your compression and fuel pressure.

Jan 17, 2011 | Hyundai Sonata Cars & Trucks

2 Answers

I have a 99 grand am SE 2.4 4 cylinder and my problem #2 misfire, repalced spark plugs with AC delco rapid fires, replaced coil packs, replaced coil pack housing, changed spark plug boots, had ignition...

A misfire doesn't always have to be ignition... it's just the most common cause. Faulty or plugged injector, low compression. You need to check fuel pressure and test the fuel injector flow. Then check compression. If you don't have tools for these tests, take it to someone who does. Testing is much cheaper than throwing parts at the problem.

Feb 25, 2010 | 1999 Pontiac Grand Am GT

4 Answers

I have a ford explorer 99 but it's giving a error code PO306 what do u think it is

It sounds like a misfire. Check spark plugs 5 and 6. It could be bad fuel, bad plug wire, or weak coil. Check the fuel injectors as well. Other possible causes could be an egr valve stuck open, vacuum leaks, low fuel pressure.

Feb 17, 2010 | 1999 Ford Explorer

2 Answers

I have a 99 Ford Taurus that keeps showing a code PO301 #1 cylinder misfire. I have changed spark plus first, and it came back on. I next changed the wires and it came back on. I took the coil to Autozone,...

If the plugs, wires, and coil are all good then it can be a partially clogged injector, or low compression on that cylinder. It can also be a bad ECU. My cousin had a 99 Taurus with the exact same problem and it turned out to be the ECU which he had to replace. The ECU is very expensive so make darn sure everything else is good before you replace the ECU. It could be the coil has an intermittent problem and may show good especially when cool. You might try putting that coil on a different plug position, resetting the ECU, and see if you get the same code PO301. Run a compression test on all cylinders to see if you have good compression. Add a can of Seafoam Fuel Treatment to a full tank of fuel to make sure the injectors are clean. Check all wiring closely for frayed wires or loose connections. Eliminate all other possibilities before looking at the ECU itself.

Nov 30, 2009 | 1999 Ford Taurus

9 Answers

Misfire #3 cylinder

Has anyone found the problem? My 2003 has #3 cyclinder misfire and I have replaced the plugs and wires. It runs rough at idle but smooths out at highway speed. Anyone have any knowledge on this? This sounds like a common problem.

Sep 09, 2009 | Cars & Trucks

3 Answers

1997 ford f150 cyliner 7 misfire

sme problem had to have it put on computer and codes reset

Feb 05, 2009 | 1998 Ford F150 Regular Cab

Not finding what you are looking for?
Cars & Trucks Logo

Related Topics:

2,325 people viewed this question

Ask a Question

Usually answered in minutes!

Top Chrysler Experts


Level 3 Expert

77499 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22306 Answers


Level 3 Expert

814 Answers

Are you a Chrysler Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides