Solved 98 mountaineer 5.0 running very bad HELP!

[tevans720]

98 5.0 last week i was driving around for a few hours and everything was fine. Did some work in the garage for a few hours and had to run to the hardware store. Started the truck up and she ran like crap. Engine shaking like a miss fire. First thought plugs and wires. Well by then it was late and easter was the next day didnt get to it till Monday. Well after the change still crappy running. So I changed the fuel filter and cleaned the mass air. No change. Checked for spark on the coil packs all have spark. Checked the PCV all good there. Checked for vac leaks none found. During that I noticed a small hole in the EGR tube I repaired that but still running like crap backfiring out the exhaust, engine shaking badly at points.

Only code it throws is a EGR high flow after I fixed the hole but was having problems before that.

Oh forgot I also changed out the FPR on the fuel rail as well. No change of course.

Now I'm lost I have no idea what to do now. I have searched the internet high and low and never find anyone that will post their solution.

Please Help! I do have a back up car but with fishing opener right around the corner I need this to tow the boat.

 

[tevans720]

Anyone? I have no clue what to do.

 

[1998Exp]

You did not provide any history of this vehicle or even mileage. If it's fairly high, I would suspect a problem with the basic engine, perhaps a skipped timing chain. Could make sense to perform a compression test.

Anyone? I have no clue what to do.

 

[tevans720]

I would suspect a problem with the basic engine, perhaps a skipped timing chain.

While sitting? Ran perfect when it was shut off.

Say the chain did skip a link how does a guy diagnose this? I'm not really going to spend a day tearing the front of the motor apart to find nothing wrong.

 

[Turdle]

Is there a chance you got some bad gasoline? How recently did you fill up?

 

[tevans720]

Well that was my thought at first. See I worked at a junk yard until just recently. I would use all the gas from the junkers. Didn't pay for gas in 5 years. And I have ran some god awful stuff LOL.

But I have ran say 3 tanks of "good paid for" gas since. Its been on the back of my mind that the fuel pump might be on its way out. But can't see how that would make it shake so bad. Right now the tank has maybe 4 gallons of good fresh gas.

Bad injector? How do I tell which one if it is?

 

[crunchie_frog]

Have you done a fuel pressure test? Why can you not clear the high EGR flow code, is it a bad flow sensor, did you try to replace? Is your EGR valve good? How about a vacuum test, could you have plugged cats? Did you do a compression test when you did the plugs? You could check the timing with a timing gun to see if the chain slipped, I guess that could happen, but does not seem likely to me. Just my two cents.

 

[tevans720]

I'm not sure why the EGR code is there but I'm 99% sure that's not the problem as the code didn't come up till I repaired the hole.

Fuel pressure and compression test is next on the to do list just busy at work and I HAVE to watch Minnesota Wild hockey! LOL

Plugged cats could be a possibility but wouldn't that throw a O2 code from the sensor after the cat?

 

[tevans720]

fuel pressure fine. compression fine. tore apart the front of the motor and the chain didn't jump. Whats left crank sensor? The crusher?

 

[Bobmbx]

take a look at your MAF. You may have damaged it when you cleaned it, or the connector isn't seated properly.

The backfiring would tell me you're getting plenty of fuel.

 

[crunchie_frog]

Hi Tevans, ever get this figured out? I could be off, but I was thinking if you ran sour gas for a long time you could have plugged up your catalytic converter and that would give excessive backpressure to your exhaust which could cause running rough and could give hi EGR flow. Or, if your EGR was stuck open or partially open that would make it run rough as well. Just curious why you are not getting any codes other than hi EGR flow.

 

[tevans720]

If I get the front end put back together before the Wild are on at 2 I'm going to pull the O2 sensor before the cats to rule out a plugged cat.

As for the EGR I'm going to search eBay or something and order a cheap EGR and tube. Napa constantly gives me the wrong parts and I'm sick of driving 30 miles to O'Reilly's or auto zone

I'm also going to pull the injectors and clean them up and make sure they are all spraying and working properly.

 

[bill06447]

"Did some work in the garage for a few hours and had to run to the hardware store. Started the truck up and she ran like crap" Was the work you did on the truck? If so, what?

Bill

 

[tevans720]

Didn't work on the truck at that time. Was doing some welding on my smoker I'm building.

Pulled the O2 sensors. No change. I gotta have a clogged injector or that EGR is screwing things up. Just can't believe that EGR though. I've completely removed EGR's before and not had issues.

 

[tevans720]

Think I might have it! Bad injector. Pulled them out to clean and the first one I pulled doesn't click spray or anything when hooked to the battery. I pulled another just to make sure I wasn't the problem and it clicked and sprayed carb clean.

So waiting till tomorrow after work to buy a new injector and hopefully were golden.

I'll post the results so someone else may benefit from this.

Pulled all of them and have 3 bad ones. No wonder why this was running so bad.

 

[tevans720]

Yep bad injectors she runs smooth as silk now. So anyone else with the same issues heres one to try.

 

[Turdle]

Good news! Thanks for the update. I will mark this thread "solved"