valleyboyy

How's it's going , I'm new to the forum so any help would be more then appreciated. So I've been having this 89 f150 XLT lariat with the 4.9 ,got it a while back for a crappy Malibu with (eventually) what was a blown engine , Big Red (my f150) was a co-worker of mines they had put a new / rebuilt engine because they blew last one ( not sure if it's the same engine) but they put bigger pistons as well and gave me an extra tranny . So fast forward, she's treated me more than great and I always take care of maintenance regularly, bt just recently she had cut off out of nowhere , she sat for a min bt I changed plugs and wires, as well as ICM next to distributor and she was running like a river, now it's like I can't get past 1 rpm in any gear even in neutral, If I stay in a gear to try and get rpm higher , it will somewhat shake and won't exceed 1 rpm even after I shift in another gear . It has this loud sound that I think is air loss , a friend told me upper plenum gasket or something,, any help would be great.

montier1738

id check for vaccum leaks first if youre able to hear that much air from in the cab schould be able to hear that fairly well from an idle under hood the plenum gasket is cheap i wouldnt want to take it off just guessing tho but its not hard to replace may be fuel regulator line left mine of by mistake idles like a turd and barely stayed running

valleyboyy

Well could it be possible that my cats are clogged , how I said that it was from South Dakota, it never had them until it big red came to Cali, could that even matter. I got under big red and checked all and everywhere, and nothing .. although all the "airloss" is coming from back by firewall and nothing coming from exhaust tips either.

montier1738

it could be but that wouldnt explain air sound if cats are clogged they would be glowing red from heat after running and it would of came with them orignally how long have they been on their? are you hearing an exhaust leak possible manifold cracked or maybe not connected right where manifold connects to pipe and is their no air pushing from tail pipe at all? you can take the cat of and run without its free to do and would tell you if its clogged or not

valleyboyy

Yeah so big red got broken into and I had to buy new battery and cable 😑😫 gotta put a new window I got too , is it easy to install a new window on passenger side and can I use a window from a manual roll up (I have electrical) but in the morning I wanna get big red back running , I tried to see if the cats got red but nothing ,it sounds like its coming from back by firewall , and there was no smoke coming from tips , I tried hitting the cats ,a friend told me too see if it made a difference, it did a lil bit.