1989 c1500 long bed single cab 5.7 build log

[brinx182]

Bought the truck with 150k and already driven it to 160k. So far I’ve been fighting a rough idle issue and have replaced
Fuel pump (stock unit)
Tpms sensor
IAC sensor
Coolant temp sensor (for ECU)
Distributor
Ignition coil
Plugs and wires
Spare tire
Rear shackles (0/2)
Exhaust (straight pipe)
Leaking EGR (delete)
Intake manifold gasket (vacuum leak)
Air filter and snorkel delete
Grill and front deflectors painted
Wheels painted
New tires (stock size)
Tbi rebuild
Reset timing to stock
Checked for vacuum leaks

I PLAN TO address oil leaks with
Rear main seal
Oil pan gasket
Oil pan
Oil pressure sensor

FUTURE PREVENTATIVE
diff fluid change (Leaking)
Diff cover and gasket
Trans fluid drain and fill
Front brakes
Brake bleed
AC service
Radiator
Egr reinstall

FUTURE MODS
Fan swap to electric
Speakers (maybe head unit)
Full (interior out) cleaning
Painted roof (maybe hood)
Ultimate tbi mods
Bilstein shocks

 

[PlayingWithTBI]

Shine a flashlight behind the injectors and see if you have a nice even spray with no drips while idling. What is your fuel pressure? Should be 9 - 13 PSI, according to GM but, it'll run a lot better if it's 11 - 13.

 

[brinx182]

Injectors spray nice and evenly in a cone shape. It’s more of a random rough idle on start up. It happens sometimes when it’s a cold start. Has happened on a hot start. It idles down nicely unless of low on coolant, which I think is where the coolant isn’t properly reaching the CTS for the ECU, because then it idles high and makes a vacuum leak sounding noise but it’s coming from the IAC and doesn’t respond to being doused with carb cleaner

 

[brinx182]

And the fuel pressure is at 13 since the regulator rebuild and fuel pump

 

[brinx182]

Bought an injector spacer to be put on today and I may have found my issue. The injector housing wasn’t on tight and there was a gas leak around the regulator area. After the install I started it up and let it idle. No issues since