the first thing to do is pull apart the computor connectors at the back of the right valve cover / these connectors if not in TIP-TOP shape will give the ECM false readings / like the TEMP sensor

 

will check that out when i get home today.. what would be the second thing if the connectors look ok?

 

When is the last time it had a tune up?  Plugs, wires, cap rotor, timing?

 

plugs and wires are basically new..  cap and rotor not sure... what should the timing be set at?  that just rang a bell by the way... the previous owner i think might have messed with it from what i can remember but not sure....

 

8-12 btdc I believe

 

sounds like cap or wire issue to me ....poss timing
or vacc leaks ,egr hanging open ?

 

The timing should be listed on a sticker under the hood (unless it has fallen off by now.)  It will also tell you what RPM to check it at and on most trucks, you need to disconect the vac advance.

 

I would check fuel pressure. It sounds like a failing fuel pump to me.

 

got home today.. decided to do the valve cover gaskets first and a leaking exhaust manifold gasket... 

when i first started the truck today it backfired through the throttle body and cut off as soon as it started up.. then it started right up... so tempted to just rip out the throttle body and crap and go with a carb...

 

how does it run when you get it goin ? hows the power,idle etc

 

seems to idle ok.. but if i goose the pedal at idle and release .. it revs up on its own... but once it warms up and going down the road it seems ok.... until i come to a stop and give it moderate pedal to take off,  it will cut out on me and stall and is sometimes hard to crank after that... now if unplug the coolant temperature sensor it does not stall on me... but of course it is hard to crank up that way when cold

 

if thats the case you are runnin lean vacc leaks,fuel pump or filter ,o2 sensor can be causes the others may even know a few others to check

 

i had noticed that the throttle body is black from running with the.. coolant temp sensor disconnected... and light black smoke on moderate acceleration

just really curious on why it doesnt stall with the coolant sensor disconnected?

 

when you disconnect the ect sensor the computor thinks it is
-40  so it richens the fuel mix

 

oh ok...  i am kinda leaning towards the fuel pump also... just confusing as to how it want stall with a sensor disconnected but could still be the fuel pump... when i got pissed off with it today , i floored it after i got going  it popped and stalled very briefly a few times but finally surged ahead.. which feels like it just isnt getting the gas at certain loads ..

 

you need to check your fuel press first ... other wise its just guess work

 

i know...  i have a problem sometimes of "throwing parts at a problem"    can get expensive that way

 

Check the timing also mine did that when it was set at 10 btc its now around 15 btc and it runs great any less and from a stop trying to get going it was slow and would hesitate and almost stall.

 

going to check that also...  just finished up putting the new valve covers gaskets and manifold gaskets... fired it up..  small pop out of the throttle body again and stalled... started right back up again... sounded pretty good... nice and smooth... but like before...  i reached over and gave it some gas in park... let go... and the idle reved up and hanged there for about 3-4 seconds....  tommarow i am gonna try and get a fuel pressure gauge and test the fuel pump  and go from there

 

well guys..  had to advance the timing a little bit.. and the stalling has stopped.... i guess time will tell now.. it didnt help with the throttle hanging... giving it gas in neutral and letting go... you could see the idle control piston actually giving it more gas and then it would hang for a few seconds and idle back down?  very odd.... so what a did was cut off part of the piston and screw... to where i could manual set the idle at around 700 rpm with the sensor still hooked up.. kinda acts like a stopper.. seems to be working so far as it is not hanging... who knows.. might have been something very simple.. maybe someone knows the answere to this as i have a spare sensor i could still use

 

You're on the right track with the fuel pressure.  If that is normal, you could check the coolant temp sensor for ohms with a digital multimeter and compare it for spec. 
Other stuff to check:  If so equipped, there may be a throttle body temp sensor (TBTS) , towards the back of the throttle body, near where the fuel line enters.  You can check this for ohms too and compare to factory spec. 
Next, and I think its one of the above, would be the Hall effect sensor.  It could be  a combo of the Hall and TBTS (if you have one), which it was on my '88.

 

specs:

coolant temp sensor:
7000-13000 ohms @ 70 degrees F
700-1000 ohms @ 200 degrees F

tbts:
5600-14600 ohms @ 70 degrees F
400-1500 ohms @ 200 degrees F

 

Did you set timing with coolant temp sensor unplugged?
Timing chain and gears in good shape?
I'm sure you replced the fuel filter?

Cutting the plunger on the Idle Speed Control(ISC) motor may cause problems in the long run. Wait and see what happens. It is best to just replace those and set them by the book and live with the little quirks that TBI gives you such as a real high idle at startup.
Cheapest place for a new ISC is www.rockauto.com TRU-TECH Part # SA4T {IDLE SPEED CONTROL MOTOR} $56 plus shipping.

Timing Adjustments

NOTE:Â Check curb idle speed and adjust if necessary before proceding to the following procedures.

Place transmission in neutral and turn OFF all lights and accessories.
Connect timing light to number 1 cylinder. Refer to timing light manufacturer's instructions for proper connecting procedures.
START engine and allow to warm up to normal operating temperature.

Disconnect coolant temperature sensor electrical connector. The CHECK ENGINE lamp on the instrument panel should illuminate once this sensor has been disconnected.

Check timing by pointing timing light at the front crankshaft pulley. If timing is within 2° of specifications do not adjust. If timing is incorrect, loosen distributor hold-down bolt and rotate distributor housing until correct timing specification is obtained. Refer to Ignition Timing - Specifications - Electrical See: Specifications
Tighten distributor hold-down bolt, and recheck timing. Reconnect coolant temperature sensor electrical connector, and erase any fault codes that may have been set.

Recheck idle RPM.

NOTE:Â There is an additional socket next to the timing scale, it is a socket for a magnetic timing probe. Do not set the timing through this socket with a standard timing light. This socket is positioned 10 degrees ATDC and will yield inaccurate timing specifications if used with a standard timing light.

 

Chump, I have had my 89 Ramcharger for a couple years and my Idle Speed Control revs up my engine for a few seconds and then gradually brings the rpm's down.  Is this right or is my ISC gone bad too? 

 

Chump, I have had my 89 Ramcharger for a couple years and my Idle Speed Control revs up my engine for a few seconds and then gradually brings the rpm's down. Is this right or is my ISC gone bad too? Â

Sure you don't have a bad O2 sensor? Check codes. Once warm, the ISC should maintain a steady idle unless your AC is kicking on/off.