'95 TBI 305 running issues

[Truckman4life]

I have never really messed with TBI much. I have a '95 Chevy truck at work that has a 305 in it. Still obd1 so I can't hook to it with my scanner but I get no flash codes. It died the other week and I ended up finding the ignition module had failed in the distributor. Last year I resealed the intake manifold for a coolant leak and replaced the entire distributor and coil. The new module failed so I swapped the old one back in and it ran great. They brought it back to me yesterday and it is hard to start and runs crappy. You have to give it throttle to get it to run and it idles at like 400-500 rpm and if I crack the throttle too fast with the air cleaner off it just dies. Any direction to go? It doesn't have a ton of miles maybe 130K but mostly hours on it but usually a great truck.

 

[Bent77]

Check the tps signal is actually sweeping through to 5v correctly

Clean your IAC

 

[Truckman4life]

Check the tps signal is actually sweeping through to 5v correctly

Clean your IAC

Heading to Napa to get a throttle body rebuild kit in case and a new iac and a few other things. If I pull the pcv out and then remove it from the vacuum line with the engine running it picks up rpm due to the vacuum leak I create. I'm thinking it might not be getting enough air at idle through the IAC. Do you just back probe to check tps if no scan tool?

 

[Bent77]

Yes you can, but let’s do the IAC first and see where you go

 

[Truckman4life]

Bought a rebuild kit for the throttle body (gaskets and seals and fuel pressure regulator diaphragm) and a new IAC. Pulled throttle body and cleaned it and rebuilt it. Installed new IAC and installed back on the engine. Fires right off with no throttle input and idles perfect. Thanks @Bent77 I'll test drive in the am after I replace oil cooler hoses.

 

[amelbeach]

60 PSI doesn't seem all that high to me really. Am I the oddball out?

Does the gauge max out as you increase RPMS?

I would check with one of those screw on to the oil filter mount and check the actual pressure rather than a gauge and wiring that's 24 years old.