So I bought a non running 1996 Ram 1500, 4x4 5.2L and I just can't seem to get it started. Changed the cap and rotor, plugs, and IAC valve. The struck will start up if it's been sitting for a couple hours but I have to hold it at WOT for it to just idle at 1000 rpms which it very roughly holds. I checked the firing order on the cap and its all correct. I got the po505 code when I put my scanner on it. If I let it stall it's real hard to get it fired right back up. I checked compression, 120psi all around. Checked fuel pressure at the rail, 45psi. and did the old spark check test. Got spark on all 8 wires. My next idea was to take out the throttle body and clean the IAC passages. I love playing with someone elses headaches haha Anybody have any ideas?

 

Bump.

 

That 505 code is an indication that the PCM is seeing a short to ground or a short to voltage in the idle control motor wiring circuit.You already changed the IAC, so it could be wiring, or heaven forbid a bad IAC. I have had to return parts many times until I found one that would work. I would def clean the mess out of the TB, make sure the passage is clear. Also check this out https://dodgeforum.com/forum/2nd-gen...um-thread.html
I have seen a completely blocked cat cause the same problem. If the plenum is blown and has been driven for a long time that could def be the problem.

EDIT: Is this the same problem you were having when you bought the truck, or would it not run at all then?

 

Truck hasnt ran since i bought it, lk I said I love coming up behind other ppls problems haha. I did spray the crap outta the throttle body with 2+2 and it didnt budge an ounce. I did read somewhere a clogged cat could cause this to so I'm going to take the pre cat o2 sensor out and see what happens. Hopefully it works.

 

Pull the O2 sensor (pre cat) and see if it fires. If it's a plugged cat the removal of the sensor can help it releive the back pressure.

I do not think it's exhaust causing this problem, I would guess it's a lack of fuel since you have to keep on the throttle to keep it running. When it doesnt want to start, try having a assistant tryt to start it and see if you can spray some starting fluid in the throttle body and see if it wants to start. Be carefull...

I have also used a small amount of gas, very small but that is a little more dangerous and you could flood it causing it to not start at all too.

 

It's getting fuel, like I said it has good fuel pressure, 45 psi. And it doesnt want to start nemore than before when I spray starter fluid in it. I havent put a noid light on it to verify if my injectors are actually working.

 

i would pull the pre cat o2 out and try to start it my 99 had the same issue and mine was a clogged cat and if it is you can get a bolt up magnaflow high flow cat for 216 free shipping just a heads up

 

Well it wasn't the cat. Pulled the pipes off the manifolds(o2 sensor was giving me a fit to come off) Still didnt want to start. I checked the spark again for ****s n gigs and i got yellow spark. I just put a new coil on it so that aint it. My next step is to try changing wires and or the cam pos sensor under the rotor.

 

use a test light, or a noid light, to see if you are getting injector pulse.

 

Yea, thats my next move.