I posted a few days ago about buying a '99 with 202k miles. Turns out it is 205k.

Anyways, I still have concern about the power. There is no Check engine light or anything. It doesnt hesitate or anything like that. I did notice that driving home at 70mph on the Interstate it had to drop into lower gear going up a couple hills...but again...I am used to my diesel...so maybe that is normal on this truck?

It has 205k miles...so I am sure it needs new plugs. With all the issues I hear, is this ok to DIY or is best left to the dealer?

Lastly the exhaust was converted to 2 straight pipe type mufflers...and then its cut off right behind the mufflers. There is no tailpipe. That gets fixed on Thursday. I am wondering with no tailpipe and 2 wide open muffflers if there is likely some kind of performance issue. I have heard something about not enough back pressure etc...but I dont really know what that means, or if its anything I should be worried about. Truck seems to run good...but maybe not really smooth...that being said the rough doesnt seem to come from the engine area. I think its almost like mini backfires at times, can the exhaust make that much difference?

Thanks.

 

yea, definitely get that exhaust fixed.

as far as plugs go, it's a do it yourself if you have the time. plenty of write ups if on here. all the 5.4/4.6 write ups are basically universal.

do a coolant flush while you're at it.

 

yeah...I want the temps to break a little (high of 6 today) but I know I need to do coolant, tranny and other fluids...

 

So your truck has true duals? if im reading that right. You will have to check with the exhaust gurus, but i think you tend to lose a little low end with a setup like that, but i gained a little mpg with mine.....so with that many miles id rather have the power back.

 

Say what? Dropped a gear on the hills, empty ?? You sure that's a 5.4L ?

Yea, it will feel like a different truck when that exhaust unf' ed. Unless you tune it, custom tune it @ speed shop on a Dyno for best results.

Yea, your must be not tuned to run that set up. I've driven a few like that lol. Gutless wonder taking off, then mid-range, go flat, up top they try, but tire easily lol. Man, that must of been a depressing ride home lol.

It can be fixed. Running that bad,I bet it's cat-less, - or you have your forward cats, just the house , (but nobody's home)-, ie gutted.. Rears aren't even there.

Factory system -

 

Yeah...my exhaust looks nothing like that at all. I am pretty sure someone has turned it into dual exhausts because there are 2 straight pipe type mufflers and they are cut off between the start of the truck bed and the rear tires.

So bad exhaust can cause it to have some power issues is what I am getting? I might be able to get that fixed today...waiting to see if i can get into the shop. Other wise its Thursday.

 

Did you happen to have a compression check done before you bought it, that many miles I would have. Focus on a good tune up... New motorcraft plugs, a set of cop's, air filter, fuel filter, fluid flushes, clean the TB and elbow (that's something that is normally never done in the trucks life, if that is the case... it should be the most rewarding) Clean MAF sensor, maybe 02's for good measure?, go through all the hosing and vacuum system to check for any leaks etc... Get it dialed in the best you can. Dual exhaust is not a bad thing, if its done right and tuned. If just hacked apart and pipes welded in place and dumped out the back, there could be some loss of low power. Thing is, you didn't buy a diesel. The 5.4 is a great engine and the F150 is a great truck, but by no means is it the most powerful thing out there. Once you get all those things changed out and the truck is back to its old self, it will grow on you. Especially if you throw some E fans and a tune on with a good exhaust.

 

I climbed under it. There are true dials and no x or h pipe. It looks like cats are there although I don't know if they have guts or not.

I did not have a lot of choice on the vehicle...long story short my wife was hurt and out of work for a few months...so this was a truck that i could sell my diesel in and get with no cash. I know it's not perfect but the body has no rust etc and the interior is pretty good as well...so if I can get it solid I'll be ok.