93 s10 350 wont rev past 3000rpms idles at 500rpms

daddydec21 · Member Joined: 26 Oct 2010 Posts: 50 1648.84 points

hey guys new to the forum names paul thanks for any help in advanced. i got a 350 motor out of a 1990 k5 the motor was rebuilt .010 over when i got it. installed it into my truck. (93 s10 standard cab short bed) motor sounded great at first ran at 800rpms. could rev it to round 4800rpms. all of a sudden its idling at 500rpms.and revs to around 3000rpms. acts like a rev limiter at 3000rpms. i used the orig 4.3ltr wiring and comp. truck was automatic 4l60e i put a nv3500 out of a 2000 s10 extreme. fuel pressure is a constant 11-12psi and i put a new coil on it and it does the same thing. disconnect the tps and made a difference but for the worse. any help would be awesome thanks guys also new fuel filter plugs wires and gas all that was done before the problem started and timing don't make a difference only for the worse right now its set tdc 0 deg the truck will sit a idle smoth at 500rpms

10sec.et · Posted: Fri Apr 15, 2011 1:59 am Post subject:

does it only do this when its hot or all the time ? vacuum leaks under the throttle body ? clogged MAP sensor port in the T-body ? thats just what immediately comes to mind. the 4.3 computer/harness is the same as the 5.0 and 5.7 so that is a non-issue. injectors are also known to take a crap after a decade or two. damn expensive to replace too ($250 each last time i checked). i have learned to hate TBI because of so many that, for no apparent reason, had weird quirks that couldnt be fixed. on more than one occasion i have (after countless hours of diagnostics on everything on the truck) swapped T-body, computer, distributor, and ign module, with a known good vehicle, and still not been able to figure out why it would fall on its face after it went into closed loop.

daddydec21 · Member Joined: 26 Oct 2010 Posts: 50 1648.84 points

it does it warm are cold not difference

jeep_406 · Posted: Fri Apr 15, 2011 10:56 am Post subject:

Just wondering what the TPS is reading and the fuel pressure seems low to me. Are you getting any codes?

Just a couple of thoughts from a guy who hasn't done any diagnostic work in years.
Welcome to SMOKEmUP.

daddydec21 · Member Joined: 26 Oct 2010 Posts: 50 1648.84 points

tps was disconnected and made my problem worse so thats functioning and the psi for the tbi is 9-13 psi its staying around 12 what about timing chain?

jeep_406 · Posted: Fri Apr 15, 2011 5:23 pm Post subject:

My thought on the TPS is that it works on a reference of 0 - 5 volts. If you're only seeing a couple of volts at full throttle that could effect performance.
The way I'd check Timing chain play is to remove the dist cap and walk the engine back and forth with a bar on the crank. If there is much play in rotor movement in would be from a loose chain.

daddydec21 · Member Joined: 26 Oct 2010 Posts: 50 1648.84 points

ok i did the timing chain and gears anyway and that did not fix the problem although the timing chain was extremely loose. so i pulled codes. and the codes i got which i did not understand were 13 14 15 16 18 19
yes the 02 sensor is not hooked up because i did not weld the fitting yet. that's out i know that's not gonna do it

coolant sensor is disconnected because i hooked up a Manuel gauge in its place.

no clue about 16 but i did install a tach??

17 and 19 no cam are crank position sensor? no clue about that one either

13 oxygen sensor circuit open
14 coolant sensor high resistance or shorted
15 coolant sensor circuit low or open
16 direct ignition system (DIS) fault in circuit
17 cam position sensor fault
18 crank or cam sensor error
19 crank sensor circuit fault

jeep_406 · Posted: Fri Apr 15, 2011 7:21 pm Post subject:

Don't have time to look right now as I'm going out the door. I think I mentioned earlier that I haven't done any diagnostics in a long time but my first thoughts are that with ODB1 Without Coolant temp sensor or O2 you're going to get what was referred to as limp home mode. I believe also that when you got a bunch of codes you started with the lowest number first.

daddydec21 · Member Joined: 26 Oct 2010 Posts: 50 1648.84 points

ok i pulled the codes agein and got 43 59 66 67 73 82 not worried about 66 67 73 there ac but the limp mode your talking about how can i fix that? as i said befor it ran fine for about 8 gallons but you can tell it was burning alot of fuel from the smell and white smoke..

10sec.et · Posted: Fri Apr 15, 2011 11:15 pm Post subject:

codes are a good thing. the ECM is capable of recognizing a fault. first thing, clear all the codes. take both battery cables off and touch the terminals together for ten seconds. this will clear codes as well as adaptive memory. start it back up and see which code(s) come up first. from there we should be able to determine what direction to go in.

daddydec21 · Member Joined: 26 Oct 2010 Posts: 50 1648.84 points

ok im gunna go do that now also dont know what all you read hear but its acting as a rev limiter around 3000k in neutral and while driving it was auto i made it a 5spd with nv3500

10sec.et · Posted: Fri Apr 15, 2011 11:48 pm Post subject:

without a load on the engine, most will act like its hitting a limiter at 3000 rpm (it actually is). most computers are programmed that way to keep people from putting the rods through the side of the block while reving it in the driveway. im more concerned with how it acts while driving.

daddydec21 · Member Joined: 26 Oct 2010 Posts: 50 1648.84 points

ok i had the battery dis for about 2 hours. i still touched the terminals together though stuck them on started it shut it off read the codes codes are 43 59 and 82 what the hell is 59 i cant find that code no where and cant find out how to fix code 82

daddydec21 · Member Joined: 26 Oct 2010 Posts: 50 1648.84 points

yey that bothers me to lol wish it would just work

10sec.et · Posted: Fri Apr 15, 2011 11:55 pm Post subject:

i still have a resource, assuming the password still works. ill find out later tonight.