2thousand5.4

Ok so today when I started up my truck to come home from walmart I noticed my idle was rough but I didn't think much about it and started to drive anyway. I got about 3/4 of a mile down the road then the CEL started flashing and the engine temp went almost all the way up to red so I immeadiatly pulled into a parking lot to let it cool off. Then I noticed a strong exhaust smell. Once the truck cooled off I drove the rest of the way home going 35 mph with the engine temp staying pretty high. The manual says the engine is misfiring so I'm pretty sure that's what it is, but its not like the other misfires I have had (bad COP). Two days ago the truck hesitated getting up to 45 mph, but that only happened 2 times. It also ran fine on the way to walmart the problems begain on the way home. The only thing I have done to the truck is replace the muffler with a magnapack and I just did that 4 days ago. Thanks in advance but this truck os really starting to pi$$ me off, it constantly blows COPS and the o2 sensors go bad to. I have only had this truck a year and I really like it I'm just tried of its problems I'm almost ready to get rid of it.


On the plus side the excess exhaust heat is helping break in the new magnapack quicker


*EDIT* I'm going to clean the MAF, throttle body, and change the fuel filter oil and oil filter. The oil and oil filter only have 2000 miles on them, I was using 10w30 but ill change back to 5w30 like the manual says.

2thousand5.4

Bump

ellis4pa

The overheating part, that's what worries me. My personal experience is misfiring doesn't cause it on it own.
The engine can't get rid of the heat, sounds like its not exhausting right, and since you have had exhaust work done, I would like to nominate your cats as your problem.
Clogged cats can give you a bad idle, power loss, overheating and a bunch of codes.

What year is your truck?
Any intake mods?

2thousand5.4

Its a 2000 with the 2v 5.4 and I was worried about the cats too, but all I did to the exhaust was a simple muffler swap I didn't go any where near the cats or even the Y pipe. I will run up to advanced auto on Tuesday to get them to run the ODB2, I have a strange feeling my MAF is dirty and that is what is causing the problems tho. I have had misfires before but this is the first time the engine temp went way up. My mom drove it the rest of the way home after I pulled over (I'm only 16) and she said the seatbelt light started blinking? I have never heard of that before. although I never did see the seatbelt light blink ill take her word for it, the CEL was also blinking but then changed to a solid CEL light. So you are thinking the muffler swap is what is causing problems? We did have the hood open most of the time and it was drizzling so maybe water got some where? It the engine wasn't like soaked it probably got 5 min of light drizzle near the end of the muffler swap. But it ran fine the day of and day after the swap it was the 3rd day when the problems started. Thanks

2thousand5.4

And no there has been no intake mods done. From what I can tell the previous owner didn't take care of her well because from what i can tell there is still the stock fuel filter, air filter, and idk if the plugs have been changed (I have 168xxx miles)

ellis4pa

Usually a steady CEL is an exhaust issue, and when it starts flashing the problem is more serious, like an engine issue.
I was thinking the muffler swap may have shook something up or damaged the cat core, I imagine there was some cutting and manipulating to remove and install the mufflers.
Cleaning the MAF and throttle body is an excellent idea as long as you use the correct cleaners. But I'm still thinking that the issue is deeper. Your truck is designed to haul thousands of pounds and not overheat, so a trip to the store should not have caused an overheat situation unless your cooling system is failing. So, did your engine overheat before the CEL came on? Or after.
You said the muffler swap was done 4 days before, was it driven at all between then and your problem? I'm going to assume yes for now, so the light rain should not have been a problem.
Oh, and 168k miles would have wore those cats in good, especially since you've had miss fire issues in the past, those are hard on them.

2thousand5.4

The CEL and the over heating happened at the same time. The manual says that a flashing CEL is a bad misfire and can cause the engine to overheat, the cats to be damaged, and can cause a fire. This misfire isnt like all the bad COPs that i have had though, they didnt cause the exhaust to smell and the truck to over heat. The truck was drive after the muffler swap before the problems happened. I just got back from vacation that's why I was taking so long to reply. (Truck was at home, we left Saturday). Anyways, I was reading another thread and the discribed the exact same conditions and they just had a dirty MAF. So tomorrow ill go to the auto parts store and get MAF and throttle body cleaner. Ill also cheack the cooling system tom

2thousand5.4

I just checked the engine coolent box and it is bone dry know what could have caused this? Money is extreamly tight right now so hopefully its a cheap fix or its gonna sit for about 2 1/2 months.

2thousand5.4

OK so I just filled up the coolant cleaned the MAF, but I still have to clean the throttle body. Although the TB didn't look that bad from the intake side, the valve fully closed without sticking. When I started her up the CEL stayed off and the idle smoothed out a little bit. When I rev it, taking it up to about 2,750 RPMs, it did still feel like I had a slight misfire. The stinky exhaust also went away, although I haven’t taken it on the road yet. I did notice coolant dripping steadily from the engine, that’s why I didn’t drive it. I found that it was leaking from the crankcase (I think that what it is) meets the engine. (Where the black part where you put in the oil meets the engine) near the front of that seam I’m talking about it looks like there is a gasket popping out causing it to split and leak. Would that coolant leak cause it to run rough? I also noticed that the lower line in the intake is pretty loose where it meets the line that attaches to it, is that a vacuum line? I’m worried this is going to get pricey real quick. Sorry for the inexperienced tech talk I’m pretty new to engines. Thanks

ellis4pa

Well, damn.
The overheat may have caused your head gasket to blow, from what I can tell where your describing. If this is the case, its expensive now. Check your oil, if its looks like 'chocolate milk' don't run it anymore, the coolant is in your crankcase.
Do you have any idea as of the last plug change? When you replaced the cops did you replace the boots too?