Misfire, codes P0302 and P0303

ABGREEN

MEMBER
2000 FORD ESCORT
2.0L
4 CYL
2WD
AUTOMATIC
100,000 MILES

Misfire on two and three (p302 and p0303). Checked for vacuum leaks, replaced plugs, wires, coil pack, switched injectors with one and four. Compression is good, codes always come back.

Saturday, February 2nd, 2019 AT 3:08 PM

6 Replies

SEVAG P

MECHANIC
405 POSTS

Hello thanks for using 2CarPros.

Checking actual values for misfire counter if its count at only at idle speed or at all conditions.then run our guide:

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

Thank you let us know the results.

SPONSORED LINKS

Was this

answer

helpful?

Yes

Sunday, February 3rd, 2019 AT 4:56 AM

KEN L

MASTER CERTIFIED MECHANIC
43,288 POSTS

Can I ask what the spark plugs looked like in each cylinder? White, grey, black?

Was this

answer

helpful?

Yes

Monday, February 4th, 2019 AT 2:23 PM

ABGREEN

MEMBER
3 POSTS

Thanks for your reply. Plugs look good (we switched plugs to 1 and 4), misfires only at speed if you stay off the freeway no codes are set, customer was able to drive for two weeks with no codes until she went on the freeway. No discernible miss until around 2,000 under a load.

Was this

answer

helpful?

Yes

Wednesday, February 6th, 2019 AT 11:31 AM

KEN L

MASTER CERTIFIED MECHANIC
43,288 POSTS

Yep, sounds like you may have a flat camshaft lobe. Lets remove the valve cover to inspect. here is a guide to show what I am talking about:

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

Please run down this guide and report back.

Was this

answer

helpful?

Yes

Wednesday, February 6th, 2019 AT 1:42 PM

ABGREEN

MEMBER
3 POSTS

Thanks, I bet you are right. It never crossed my mind, never see that in newer cars (I'm 72 so to me any thing built after 1985 is newer to me). If we ever get it back I will let you know.