Multiple Misfires

[dudleyp]

99 disc misfires on left cylinders

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Getting service engine codes p1300,p0300,p0301,p0303,p0305 and p0307. I have changed the plugs and wires,reset the codes and they come back after driving 5 to 10mins and once a while the service engine light flashes. When I step ******* the gas it hesitates. Any help would be great.

Thanks

 

[joey]

Welcome to the forum... You either have a bad connection on you fuel injectors, or a bad coil pack.

 

[dudleyp]

Welcome to the forum... You either have a bad connection on you fuel injectors, or a bad coil pack.

Hi, I read somewhere on this forum that misfire on 1,3,5,7 is caused by a bad vss. I just wanted to check with you to see how true it is or it is something else.

 

[joey]

Not true... each coil pack controls either even or odd cylinders.... I would check the wiring to them and replace if you find nothing.

 

[dudleyp]

Not true... each coil pack controls either even or odd cylinders.... I would check the wiring to them and replace if you find nothing.

Joey, Each coil pack does not control either even or odd cylinders. I just checked and one controls 1,6,7,and 4 and the other 8,5,3 and 2. you still think it is the coil pack? if yes wich one or do I need both.


thanks Joe

 

[joey]

Your correct, sorry I was thinking the plug going into the ECM. Check the ECM for dirty connections... Had a lot on my mind last week... sorry for the miss information.

 

[dudleyp]

Your correct, sorry I was thinking the plug going into the ECM. Check the ECM for dirty connections... Had a lot on my mind last week... sorry for the miss information.

Today I put seafoam in the intake manifold while the car was running and I had some liquid leaking from the valve cover on the drivers side where I have the misfire. If I had a bad seal on the valve cover will that cause the misfire?

 

[joey]

Since 1 3 5 7 are on the drivers side if this is the side that is leaking.... this could be a few things. I would hate to just guess on this, since I haven't seen this before that I recall.

Calling DiscoMike... any thoughts on this one?

 

[[email protected]]

Brewing misfire problem

Good afternoon, folks. I have read some of the posts related to misfires, but don't have my problem pinpointed just yet.

My 01 Discovery II (116,000miles) misfires occasionally upon application of throttle. Usually when I am returning to power after a coast or glide for a bit. No codes yet, but no mistaking it, misfires are quite noticeable. Seems so precise that I suspect electrical/ignition rather fuel related. I am suspecting coil pack(s) may be failing or ECU connections may be dirty.
Am I on a right track here and is there a pattern to this sympton someone can tell me about? I am wanting to find a cure before it leaves me along a road somewhere.

Any coaching will be appreciated.

Dave

 

[joey]

Check fuel pressure first.