madsky012

My 1993 F150 XL with the 4.9 IL and 5 speed isn't running right. It sometimes doesn't start unless we spray starting fluid in it and when it does start and you go to push the gas it'll rev for the first bit of pedal movement and then bogs down. When you turn the key on the fuel pump comes on and never shuts off, and we tested the spark and it was there, but there was a case where it went away after we got it back to my house and then it came back. The check engine light is on but we can't get the jump wire code flash test to work. We've tested the coil, it failed so we replaced it, we tested the ICM and it failed so we replaced it for the fourth time (so if anyone knows why I keep burning through those I'd appreciate the info), replaced the fuel filter even though the old one worked just fine, and then we replaced the cap and rotor, none of these new parts fixed the issue. I've been told to check out the mass air sensor and the throttle position sensor but we haven't worked on it again yet. So if anyone has any input on this issue and could help me out Id really appreciate it!

Chris_1

iTrader: (1)

You can test the TPS - I put a post up about feb 22 that explains it. Also a fuel pressure gauge - access is the schrader valve on the fuel rail. Your truck calls for 45 to 60 psi.
Key on engine off you should get minimum 55 psi.
Truck will do exactly what you describe if the fuel pressure is too low or if the TPS is faulty.

madsky012

I forgot to mention we checked the fuel pressure, it was right where it should be even when we cranked it a bit. It turns out that it skipped timing because when he went to get a reading of it the marks were facing the bottom when they're supposed to be facing the top, (I don't know much about reading time so I may have said that wrong). But when I search for a new timing chain to get a rough price, I can't find them anywhere, just the cover and gasket

fltdriver

Autozone has them for $13-30, I couldn't find them on rockauto, amazon has a bunch: http://www.amazon.com/s/ref=sr_st_pr...price-asc-rank

madsky012

my local autozone didn't have them, they searched them and couldn't find any anywhere except for Edelbrock for $90

madsky012

Apparently my truck doesn't have a timing chain... That's what the guy who's working on it for me said. Still can't figure out the issue is. He checked the catalytic converter to make sure it wasn't clogged and it was fine. Still no idea what's causing the issues

Chris_1

iTrader: (1)

Coil ? Sometimes people put aftermarket coils on that don't match the rest of the ignition system. Also test the tps.

madsky012

I'm letting this guy do all this work for me cause I'm only 18 and have no automotive skills other than basic maintenance. The guys brother has some really expensive snap on reader that they connected to it and they can't read any codes of any type so they're thinking that the computer may be shot.

Chris_1

iTrader: (1)

You said you tested the fuel pressure. What was it at ? Pre-94 4.9's run at a much higher pressure (45 to 60 psi) than v8's and 94+ 4.9's

madsky012

it was at 55 I believe