My "new to me" '93 F-150 XLT (302, 4X4 Supercab) has got two issues. The first is a noise that sounds like chut-chut-chut under acceleration (almost like valve slap, but not quite). The second is a drivetrain issue that only pops up during/after a hard rain.

NOISE: I've spent some time researching the noise in the forums. My best guess is that there's a leak in the headers, probably a bad gasket. It only sounds like it's coming from the passenger's side of the truck. Like I mentioned, the PO put headers on the 302 and it all ends at two cats that are roughly speaking, sitting right next to each other directly under the passenger's side of the bench in back (it's a Supercab). So is the noise really a leak at the headers/engine or could it just be the sounds of the exhaust minus mufflers? Under minor laod or coasting the sound disappears. While I'm at it, here's a quick side question- is there a way to clean out the cats before I run some new pipes and glasspacks? Brake cleaner or something?

DRIVETRAIN: After spending a few hours pouring of the forums, I think the stutter might be the MLPS. My truck is a '93, so the E4OD that it's got should have the early/problematic MLPS. The stutter only happens during or shortly after a heavy rain, so I'mn guessing water is getting in there and causing the problem. I'll be driving along and it seems like the truck shifts in and out of neutral. It does it sporadically in all gears. Sometimes from a dead stop, sometimes in thrid, etc. It's like it's hesitating, but the RPM gauge never spikes or anything, so I'm doubting it's fuel delivery or something like that. After the truck warms up (15 minutes into the drive or less) it clears right up and runs fine. If it hasn't rained in the last 12 hours or so the hesitation problem doen't ever rear it's ugly head.

So do you think I'm right? I know there's only one real way to know, but time and $$ is scarce right now. So when I do get the chance to spend a little quality time with my truck I need to make it count. SWMBO is cool with me having a project truck, but if I start throwing money at it like I was Donald Trump, then her attitude is going to sour pretty quickly. So if you all could chime in and let me know if I'm heading down the right track, I'd really appreciate it.

Much obliged.

 

Wow, 47 views and no responses? Just kind of bumping this thread back up. I think I've got the noise nailed down. It's the exhaust, or should I say, lack of exhaust. Never ran a truck without a muffler before. Sure Ihave them with bhad mufflers, but apparently a bad muffler sounds better than no muffler. No worries, a nice set of Cherry Bomb glasspacks should fit the bill quite nicely.

As for the tranny/hesitation/shift-studder- we've been sans rain for over 24 hours now and the issue is gone. When I get some free time I'll attend to the MLPS and see if that does it. Need to Seaform the oil and change it shortly anyway, so might as well knock them both out.

If anyone can think of any other possible causes feel free to chime in.

Thanks

 

The sound could be an exhaust leak. Well I guess you already figured that out. The Cherry Bomb packs should sound great.

Does the truck have factory manifolds or has someone put headers on it? Either way I recommend Percy's seal for good gaskets.

Its hard to say about the drivetrain issue. Read the codes. Even if the engine light is not on, there can still be codes present.