Need Expert Help With Misfire

[anumber1]

For the fuel pressure, there is a Schrader valve on the fuel rail that will allow you to attach a fuel pressure gauge.

 

It should be 60 to 65 psi, key on engine off.

 

A vacuum gauge will not be of much help to diagnose the intake gasket but using some throttle body cleaner or other flamible spray, you might get lucky and find a change in idle when spraying near where the manifold meets the head. (This ain't safe, it's a good way to make a fire).

 

It very possible that a leaking intake gasket could result in a lean misfire. Especially if it is leaking bad right near #1.

[kxdan01]

Thanks again, I'll be trying it all out tomorrow, I tried today but immediately got sidetracked because I had to replace a pair of thermostats and the heating element in our dryer which is too new to have issues but thank God it's fixed now and I don't have to hear the old lady bitching about it, one less thing.

 

I'm going to take the coil pack that I didn't need back and hit up the pick & save salvage yard and pull a few coil packs, injectors, plug wires, oxygen sensors, and a few other things from the vehicle like mine with the newest parts on it and it'll probably cost about the same as that one new coil pack cost at the parts store, I was in a hurry and didn't check around to compare prices because I was in a big rush, but I assumed it would cost about the same everywhere since it's such a common item, boy was I wrong, it was more than double the price I could've bought it for at the other 2 parts stores less than a mile away, but that's what being in a frantic rush does, lesson learned (again lol). I'll get it fixed somehow in the next day or two and let you guys know what it was.

 

Thanks again, if anyone has any other advice/tips/tricks please share.

 

Any suggestions on the best way to clean injectors or the easiest c way to access/remove them. I haven't really checked because I haven't removed the plastic engine cover as of yet but I will tomorrow. Thanks again for everything guys, I'm not out of the woods yet but at least I know where to look and what I'm dealing with now, I owe that too you guys, it's greatly appreciated as will any further information that may be helpful be!

Thanks again, I'll be trying it all out tomorrow, I tried today but immediately got sidetracked because I had to replace a pair of thermostats and the heating element in our dryer which is too new to have issues but thank God it's fixed now and I don't have to hear the old lady bitching about it, one less thing.

 

I'm going to take the coil pack that I didn't need back and hit up the pick & save salvage yard and pull a few coil packs, injectors, plug wires, oxygen sensors, and a few other things from the vehicle like mine with the newest parts on it and it'll probably cost about the same as that one new coil pack cost at the parts store, I was in a hurry and didn't check around to compare prices because I was in a big rush, but I assumed it would cost about the same everywhere since it's such a common item, boy was I wrong, it was more than double the price I could've bought it for at the other 2 parts stores less than a mile away, but that's what being in a frantic rush does, lesson learned (again lol). I'll get it fixed somehow in the next day or two and let you guys know what it was.

 

Thanks again, if anyone has any other advice/tips/tricks please share.

 

Any suggestions on the best way to clean injectors or the easiest c way to access/remove them. I haven't really checked because I haven't removed the plastic engine cover as of yet but I will tomorrow. Thanks again for everything guys, I'm not out of the woods yet but at least I know where to look and what I'm dealing with now, I owe that too you guys, it's greatly appreciated as will any further information that may be helpful be!

[rdnkcpa]

A P0171 says your running lean. More air than fuel is getting in there. Your computer is compensating by dumping more fuel in the cylinder. You need to get this cleared up before your cats get plugged. IIRC you got a fault code for an O2 sensor, most likely a result of your lean problem, not an actual bad sensor.

 

You should hook a vacuum gauge up, they are not expensive. Over on Ericthecarguy.com, he has a good tutorial on how to troubleshoot with a vacuum gauge.

 

Troubleshoot for the vacuum leak first before more ignition parts.

 

You can spray some carb & choke cleaner around the intake near #1, and listen for a change in RPM's. If you have anything like that, then you know you have a bad intake gasket, or the plastic intake may have a crack in it somewhere.

[kxdan01]

I know this is terribly late but I've had some internet issues and been really busy lately but I thought I'd update this and thank everyone for their input again, I greatly appreciate it.

 

Ok, so it's all fixed and running great. I made a mistake when explaining my problem earlier when I stated that the truck still have the original wires and plugs and stuff like that but it slipped my mind that it had been fully tuned up with all new AC Delco Parts, but it has been a few years. So I got access to a good scanner and got codes for misfired in #1 Cylinder, oxygen sensor & air/fuel related codes, plus a few stored ABS Codes. I checked for intake leaks and made sure all was well with the internal stuff to eliminate the possibility of anything major. So I went to the local junkyard that lets you pull your own parts (it's called "Pick & Save" in Roanoke & Lynchburg,VA) and found a few trucks like mine (they were heavily picked over, I almost gave up on finding any plug wires or ignition related stuff but finally found what I was looking for after looking at quite a few) and got a few fuel injectors, a nearly new oxygen sensor, an extra coil pack, a nice Mass Air Sensor, some extra spark plug wires just in case, plus some wiring harnesses for the injectors/coil packs and a rear brake rotor I needed also, and I swear I was totally shocked that they only charged me about $8 for everything, yes under $8, I know a lot of people don't like using used parts but I don't care as long as they work, I had to hit a few different trucks to get it all but I was prepared for the majority of the possibilities it could be. After all of that, I went to the parking lot and replaced the spark plug wire on the #1 Cylinder with a used one I had just gotten and made sure the connections were good on all injectors & ignition related components, I was hoping it would help and since it was the quickest/easiest thing to try before leaving but I didn't expect it to really make any difference since the spark plug wire I removed looked perfect & the used one I replaced it with looked pretty rough from laying in the dirt under one of the trucks I'd been pulling parts from, so I got in and started it up, PROBLEM SOLVED! It was either the plug wire or a loose connection somewhere, but I'm 99% sure it was the spark plug wire, I drove it halfway home then scanned it a few times just to see if any codes came up (No Check Engine Light) and none did, I got a can of Seafoam and filled it up with fresh Ethanol Free Gas (I use it whenever possible, it is just my preference) and it's actually running as good or better than it has in the 5 Years or so that I've owned it. So thanks again for all advice and help.

It might not be too obvious from my post & questions/answers but I'm an experienced mechanic, I'm ASE/NATEF Certified and worked in the service departments & various shops for years (mainly on mobile refrigeration/HVAC & heavy trucks/trailers/equipment, but lots of regular cars/trucks etc and building a few drag cars/motorcycles. I'm no longer in that line of work, so I have gotten a little rusty. But lately I've been doing quite a bit more mechanical stuff to my own projects and stuff my friends/family own also, my whole point is that even though I knew better, I overlooked some of the basic stuff and assumed it was something major, and all along it was a simple spark plug wire, the Seafoam really helped, there are only a few additives I'll use, mainly the Lucas Oil Stabilizer and Fuel Treatment, I don't recall using Seafoam ever, although I know it's very well regarded in the Automotive Community, I've just never personally used it, but I can honestly say that it seems to have really helped my truck, it really has and it's not just in my head or I would say so, but I'll use it in the future in my vehicles and everything else too like the lawnmower, weedeater, chainsaw, ATV, Motorcycles, etc. If anyone with a similar issue finds this post- Just don't forget to check all of the basic stuff closely, and don't make the same mistake I did by thinking that because the spark plug wires look great, or like new, that they are because that's not always the case. I'll be sure to keep everything tuned up at regular intervals as it should be. I have slacked a bit in that area in the last few years because I no longer do it everyday for a living, I may end up going back to it, I don't miss it but it's a good way to make a decent living, I finished College and kept working in the service department and doing road calls for a few years until I got into something else, but I can't swear I won't go back to working as a mechanic or driving a truck, everything else is so damn unnecessarily over-complicated I do miss clocking in at 7 or 8 and leaving at 4 or 5 everyday. The Business World isn't all it's cracked up to be with constant threats of downsizing, layoffs, etc. plus I miss the garage environment, way more my style than the Business World, but that's a completely different subject, I apologize for the long posts, I'm used to being really detail oriented and I won't waste so much space with future posts. Thanks again guys and hopefully this will help someone somehow.