For lack of a better title... Help!
05-30-2019, 10:35 AM
#1
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For lack of a better title... Help!
Hello all.
I only recently bought my first vehicle, a 1999 F150 4.6 v8 (~146k miles, 1999 Ford F150 1/2 ton P/U 2WD 8 Cylinders W 4.6L FI SOHC) As I explained in my first (introduction) post here, I am a complete newb, lol. So...
Unfortunately the truck has started running rough over the past couple months. At the moment, the issues I am having are:
A few people I spoke with seem to think that changing the plugs will resolve most of my issues, but eh I am not so sure. Then again, I don't know much about these kinds of things.
Any input or advice would be greatly appreciated!
Side note: I cannot find any concrete info on how many catalytic converters this truck had. Any info on that would be great. I am trying to figure out if it would be feasible to purchase new converters and have them installed, if I can even get anyone to do that. A lot of places have told me they won't work on the truck since it doesn't have them to begin with.
-Eric
I only recently bought my first vehicle, a 1999 F150 4.6 v8 (~146k miles, 1999 Ford F150 1/2 ton P/U 2WD 8 Cylinders W 4.6L FI SOHC) As I explained in my first (introduction) post here, I am a complete newb, lol. So...
Unfortunately the truck has started running rough over the past couple months. At the moment, the issues I am having are:
- When I hit between 40-45mph, with overdrive on, it starts to buck and doesn't want to accelerate - it takes a few seconds of nearly flooring it to get it out of it. With overdrive off, it doesn't completely go away, but it runs much better.
- I have 2 misfires atm, along with codes for the o2 sensors. The previous owner having the catalytic converters removed, so I'm assuming that would explain the o2 sensors and possibly other issues I'm having.
- It seems that at odd times the transmission isn't shifting properly. It will either shift late or be a hard shift.
- With the A/C on, it almost becomes impossible to drive at times, seems to lose a lot of power.
A few people I spoke with seem to think that changing the plugs will resolve most of my issues, but eh I am not so sure. Then again, I don't know much about these kinds of things.
Any input or advice would be greatly appreciated!
Side note: I cannot find any concrete info on how many catalytic converters this truck had. Any info on that would be great. I am trying to figure out if it would be feasible to purchase new converters and have them installed, if I can even get anyone to do that. A lot of places have told me they won't work on the truck since it doesn't have them to begin with.
-Eric
05-30-2019, 06:45 PM
#2
Senior Member
Make sure you have Motorcraft plugs in the holes. Specially in the nonPI version of your engine. Autolite plugs are hit and miss as your bound to have a few that don't like the heat range. That could occur at any given time. In general, stick with Motorcraft, you won't have a problem.
Trans tables/shift points get goofed up if the cats are removed. Usually manifests in higher rpm shifting and slips while doing so....unless the engine was tuned to run catless. They come from factory with 4 converters, you can get away with two without further modification. As long as the connections are tight, you will remain within original programed parameter margins....no tune required. You will be well down on power with no cats. That is ONLY due to the factory tune. The A/F's won't be mixing accurately. You can custom tune the vehicle to fix that or add a cat to each side.
Trans tables/shift points get goofed up if the cats are removed. Usually manifests in higher rpm shifting and slips while doing so....unless the engine was tuned to run catless. They come from factory with 4 converters, you can get away with two without further modification. As long as the connections are tight, you will remain within original programed parameter margins....no tune required. You will be well down on power with no cats. That is ONLY due to the factory tune. The A/F's won't be mixing accurately. You can custom tune the vehicle to fix that or add a cat to each side.
05-30-2019, 07:39 PM
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Hey Jbrew,
Thanks for the reply. In regards to the plugs, I believe they are NGK double platinum IIRC. For the Motorcraft plugs, I'm assuming the SP432?
As far as tuning, I know the truck has been tuned by a previous owner, I just do not know to what degree. Basically, I'm the third owner of the truck, and the first owner did the tuning - so the guy I bought it from was no help on that. All of the cats are gone, and honestly at this point I think I'd rather add the cats - I'm only really inhibited by cost at this point, and frankly I feel like I am a bit over my head here.
Thanks for the reply. In regards to the plugs, I believe they are NGK double platinum IIRC. For the Motorcraft plugs, I'm assuming the SP432?
As far as tuning, I know the truck has been tuned by a previous owner, I just do not know to what degree. Basically, I'm the third owner of the truck, and the first owner did the tuning - so the guy I bought it from was no help on that. All of the cats are gone, and honestly at this point I think I'd rather add the cats - I'm only really inhibited by cost at this point, and frankly I feel like I am a bit over my head here.
05-31-2019, 05:25 PM
#4
I'm going to assume that the cats were removed because of the ECU re-mapping (or in conjunction with it) And - assuming you're right and the tune file is still resident in the ECU -- it's unfortunate that you [now] have no way of knowing the parameters of that re-mapping. With this in mind, it seems unlikely that introducing cats is going to make a huge difference to your performance. Perhaps not worse, but probably not much better. Changing the plugs sounds like a good idea, though. * * *
However...
IMO your best course of action would be to get a dealer to re-flash your ECU back to as-built parameters. That shouldn't cost too much or take too long, and will provide you (and him) with a known baseline from which to proceed. That will also kill off the extant DTC's -- after which you will definitely get new ones -- but they'll point you clearly toward what you need to do in order to resolve the issue(s).
* * * Do put the recommended plugs in, but maybe hold off until the ECU re-flash has been done. Reason is: the mystery map may be super-rich or (super lean) which will negatively impact not only your performance, but the physical condition of your nice new plugs.
However...
IMO your best course of action would be to get a dealer to re-flash your ECU back to as-built parameters. That shouldn't cost too much or take too long, and will provide you (and him) with a known baseline from which to proceed. That will also kill off the extant DTC's -- after which you will definitely get new ones -- but they'll point you clearly toward what you need to do in order to resolve the issue(s).
* * * Do put the recommended plugs in, but maybe hold off until the ECU re-flash has been done. Reason is: the mystery map may be super-rich or (super lean) which will negatively impact not only your performance, but the physical condition of your nice new plugs.