what's happening guys??? boy am i glad i stumbled upon your site! i just bought a 98 ranger 2.5 manual tranny with 8 plugs as is no warranty... on my way home i noticed it would idle rough after some normal acceleration but after a couple of seconds the idle would get back to normal. so i stomped on the pedal in neutral and yeah the revs went up but then it never got the chance to idle, it just died with matching pinging noises plus a misfire code for cyl 4. sounded like it was running lean to me. was gonna lift this baby 4 -6 inches and start having fun but this issue is holding me back. stuff that i have replaced and checked out so far:

8 new motorcraft plugs
8 new plugwires
1 new fuel dampener (btw fuel pressure is 60psi at the rail)
temporarily covered egr passage to eliminate my doubts if the egr was stuck
replaced fuel tank cap
replaced fuel filter

any form of advice/suggestions from all of you guys would be very much appreciated. thanks in advance and MORE POWER TO YOU GUYS!

 

How many miles does it have? just wondering.

Have you checked the spark at cyl 4? Thats wierd it won't idle and is only mis-firng in one cylinder. I drove a 6 cylinder jeep 20 miles and it was only running on 4 cylinders and drove fine.

 

it has 106xxx miles and it has a funny fuel system for a motor with fuel injection. it has no fuel return line. all it has is the dampener where fuel goes throug before going to the rail. operating fuel pressure is 55-70psi according to manual.

 

Can you find out the trouble code? If you go to an autozone or similar store they will scan the code and tell you the # for free.

I only have the workshop service manual, I don't have the diagnostic service manual.

If you find out what the trouble code is exactly, I can look it up and see what exactly can cause that etc and we can go from there.

 

Mine had similar problems and it turned out to be the MAF sensor.

 

code is P0304. thanks guys appreciate it a lot.... i do think that the code is just a byproduct of something else.

 

check the gapping of your #4 plug, and the injectors

 

Ever figure this out?

 

accoring to the odb-II code p0304 cyl # 4 misfire detected flash/ON 1 or 2 misfire. ( see DTC p0301,p0302,p0303,p0304)

 

what about the fuel filter?