2002 2.7 p0304

Hi all,

2002 2.7 Auto with approximately 105k miles.

Sine ownership around 85k miles I have always used Shell gas as I've been told to use top tier gas.

Noticed I had a little rough idle at stop lights while in drive, but when put in park the vehicle would idle fine. Next I have recently noticed quite bad fuel mileage the last few fuel ups.

Went to work the other morning and received the p0304 Code CEL flashing under load and eventually permanent CEL. Checked the 4 cylinder coil pack and saw what I believed to be a hairline crack, figured that was it. Changed out with a Denso coil and Denso Plug which was sooty/black. Makes me think its running rich and a fuel injector issue?

It rungs rough during start up and does not go away.

I have not done a compression test and also have not noticed any drop in coolant.

Any questions for me or advice? Thank you.

 

Bump

 

Start with a compression test and give us the results. When you pull the plug from the offending cylinder see if she is covered with gas.

 

Ok. I purchased a compression tester. What is the proper procedure to test the 2.7?

 

STOP DRIVING IT!!!!!
or you will need $3k worth of cat converters as a result of you kicking the can down the road...
its a misfire & youre dumping raw fuel into your cats as a result.
could be anything, spark plugs, low compression, wires, coil, etc....
get it diagnosed & avoid the parts cannon...

 

To answer your question, pull the EFI fuse, remove all the spark plugs, install the compression tester adaptor, hook it up to the gauge and crank it over. There will be a point after 4 or 5 revolutions where the reading will stop rising. Write it down and do the same for the other cylinders. This test is a go-no go test. If you have a cylinder that has less than 100 psi you have problems.

As slater has said, you are probably doing expensive damage to the cat(s) driving it around with the CEL flashing. I am assuming that this is your only vehicle and you are between a rock and hard place with this.

 

Im not talking shit but amazes me some of this shit I read on this forum, in regards to people driving their vehicles around with a misfire, having no clue what it actually is & how damaging it is to the cats which are very costly & a dealer item.....
I get it, some folks only have 1 means of transportation & have to get to work....
When I say dont drive it, dont drive it!!!!
walk if you have to....
as a ford tech ive replaced 100's of cats a year customer pay for this very reason....
I loved doing exhaust work...

 

Thank you for the proper procedure. I’ll post results when it arrives.

It has been driven less then 10 miles; when it was first noticed to get back home and a little drive after the coil pack and spark replacement to see if it cleared the issue.