Get a rebuild kit. They are not that expensive. It will come with everything needed to reseal the injectors and fuel pressure regulator.
CK5
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350 TBI surging
- Thread starter Jake_C_
- Start date
Ordered one to a parts store today, I’ll rebuild tomorrow.
Cannot believe they did not have one in stock.
I had to order a lower radiator hose today, nothing is in stock.
Nothing is ever in stock around me it seems
“Rebuilt” my injectors pods. As far as the injectors themselves go all I did was put new screens and O rings on them. Looks like you need to drive out a roll pin to take the injector apart any farther and my kit didn’t come with anything for inside the injectors. I say that to say they still drip a good bit, it may be better it’s running and actually stayed running for a long time, but definitely not just a nice even cone. I feel like at this point if I could get better spray from the injectors and some fresh fuel we might be in good shape. Should I buy new injectors now? What do we think?
It will not hurt to get another set of reman injectors. Those can be a little pricey now days. The parts store will want your old ones for a core. When you insert the o-rings onto the reman injectors use a little trans oil, vasoline, or something to make them go together easier.
I’ll go that route then, should run better even if it doesn’t fix the problem, thanks.
Here’s my fuel pressure directly attached to the out side of the fuel filter. Am I reading this wrong? Is it only at 3.5 psi? That’s where it’s at during cranking. I’m going to grab a new filter today but I know the pressure is supposed to be between 9-13 psi. Just want to make sure I’m not stupid before I continue. 
the gauge range is to small, you may have gone around once. Might want to look into renting one for tbi. Ideally 12-14psi is the goal.
@Wes Harden Yeah I knew the gauge range was too low I figured if it was pegged at 10 i could assume it was close. Here’s a video with the gauge starting at 0.
View attachment IMG_8788.mov
It obviously doesn’t physically go around again. I’ll look into a better gauge to be sure im getting an accurate reading, I bought this gauge cheap for the vacuum system but it’s supposed to work for fuel pressure as well. @Blue85 i did know the fuel pump kicks in before cranking, but I didn’t know if cranking made any difference at the pump.
View attachment IMG_8788.mov
It obviously doesn’t physically go around again. I’ll look into a better gauge to be sure im getting an accurate reading, I bought this gauge cheap for the vacuum system but it’s supposed to work for fuel pressure as well. @Blue85 i did know the fuel pump kicks in before cranking, but I didn’t know if cranking made any difference at the pump.
Once the engine starts the computer will provide a ground to the fuel pump relay, and or look for a closed oil pressure sensor. if that is as high of pressure as you get I am surprised it runs at all. I thought 9psi was the bare minimum.
I ordered a fuel pressure gauge that will be overnighted to me. I’ll test it tomorrow to confirm. I didn’t notice much difference in my fuel spray pattern when I replaced the injectors but if the fuel pressure is that low I’m sure that’s the reason they’re not spraying right. I’ll know tomorrow. I did throw a new temp sensor in it today but haven’t started it since putting it in.
I am betting that pressure test with that gauge is not valid
Tested with the new gauge and the pressure didn’t even move the needle. It should have moved it a little so not sure what that’s about but the lines on the gauge read one mark for every 2 psi. I do have the gauge jerry rigged on at the moment because I don’t have an adapter that fits the fuel filter except for a barbed fitting so I’m running hose from the barb to a t fitting where the gauge is and I have other end of the T plugged. Only setup that works so I need to find an adapter. Nothing is leaking though. Regardless the pressure is super low, the gauge has a pressure release with a hose and when pressed, the fuel will just slowly push out until the pump shuts off. Fuel looks very clean thankfully. I assume the ecm runs the fuel pump for a certain amount of seconds and then shuts it off. Regardless of how I have it rigged the pressure is crazy low out of the filter. I think I’ll just go ahead and drop the tank and replace the pump, hopefully find an adapter locally today so I can feel confident about the pressure reading.
there should be a red test wire at the fuel pump relay, if you supply 12 v it will power the pump. You can test flow that way.
Well two weeks of waiting for parts, cleaning up and painting old parts, wire wheeling and painting the underside of the van where the fuel tank goes with por15, more waiting on parts and finally putting it all back together, it’s once again complete. It wouldn’t have taken so long if I wasn’t so anal about the rust but I wanted to clean up and paint everything in the immediate area around the fuel tank, basically everywhere I wouldn’t be able to reach with the tank in. Long story short I fired it up just now and it runs beautifully, no revving up and down, no stumbling. Just sits there and idles like a dream. So the problem seems to be fixed, I’m going to look at the timing tomorrow and adjust it to my liking and lock down the distributor and call it finished. I didn’t want to run it too long since there’s probably gas in the oil now with all the times I cranked it when it didn’t start so I’ll do an oil change before I drive it. Thanks a ton to everyone for the help and suggestions, funny that I spent hundreds on parts that weren’t bad but that’s the way it always goes it seems. For future reference fuel pumps don’t just stop working completely they apparently can work halfway. Also there’s a big difference in how loud the pump is compared to the old one so if your pump seems on the quiet side don’t ignore it. Some pictures:
looking good glad it's running.
