#1. Drop tank and look for a damaged sock. Could be collapsing.
2. Check for any dents in the fuel lines, or kinks in the hoses.
3. Replace the fuel pressure regulator.
4. Check that check valves are where they're supposed to be, and not where they're not supposed to be, and that they're working properly.
5. Check that the EGR valve isnt pushing open under exhaust pressure, and that the solenoid is working right. At idle, pull the vacuum line off and make sure its not sucking air. Check for pinholes or cracks in the EGR diaphragm. Take the hose off, reach underneath and pull up on the diaphragm. Plug the barb with your finger and let go of the diaphragm. It should hold pretty well.
6. Make sure the steel vacuum lines arent cracked or have pinholes, and that any vacuum lines going to the regulator arent collapsing or have cracks/pinholes.
7. Use a 1/2" hose and listen all around for vacuum leaks, especially at the base of every fuel injector to listen for cracked injector o-rings. The propane test doesnt work. The hose will amplify the leaking sound BIG TIME.
8. Swap to a different MAF, and make sure everything is right...dipswitches and chip is programmed right. Dont want a maxed out MAF.
9. Check continuity of the orange power wire going to the ECM from the battery. Unplug it and check the continuity from the battery to the connector. Right where the wire goes into the fusible link, my wires had all broken internally, but the insulation was still there, so there was no way to tell. This cured SO many drivability issues its unbelievable.
10. Make sure you have the correct gas tank cap. This is important.
11. Check the check valve for the charcoal canister. Check all lines going to it.
12. Check all fuel system wiring and relay. Pop the connector out of the fuel pump relay on the passenger side inner fender, and clean out all the hardened dielectric grease with ronsonol lighter fluid and bristle brushes. Make sure every pin and socket is CLEAN. Do it to the knock module connector as well.
2. Check for any dents in the fuel lines, or kinks in the hoses.
3. Replace the fuel pressure regulator.
4. Check that check valves are where they're supposed to be, and not where they're not supposed to be, and that they're working properly.
5. Check that the EGR valve isnt pushing open under exhaust pressure, and that the solenoid is working right. At idle, pull the vacuum line off and make sure its not sucking air. Check for pinholes or cracks in the EGR diaphragm. Take the hose off, reach underneath and pull up on the diaphragm. Plug the barb with your finger and let go of the diaphragm. It should hold pretty well.
6. Make sure the steel vacuum lines arent cracked or have pinholes, and that any vacuum lines going to the regulator arent collapsing or have cracks/pinholes.
7. Use a 1/2" hose and listen all around for vacuum leaks, especially at the base of every fuel injector to listen for cracked injector o-rings. The propane test doesnt work. The hose will amplify the leaking sound BIG TIME.
8. Swap to a different MAF, and make sure everything is right...dipswitches and chip is programmed right. Dont want a maxed out MAF.
9. Check continuity of the orange power wire going to the ECM from the battery. Unplug it and check the continuity from the battery to the connector. Right where the wire goes into the fusible link, my wires had all broken internally, but the insulation was still there, so there was no way to tell. This cured SO many drivability issues its unbelievable.
10. Make sure you have the correct gas tank cap. This is important.
11. Check the check valve for the charcoal canister. Check all lines going to it.
12. Check all fuel system wiring and relay. Pop the connector out of the fuel pump relay on the passenger side inner fender, and clean out all the hardened dielectric grease with ronsonol lighter fluid and bristle brushes. Make sure every pin and socket is CLEAN. Do it to the knock module connector as well.