High RPM's on start up

[boomdriver]

Interesting...the spring. I have no idea what that is ! Could it be from the pintle of the injector? the pintle return spring? I know the Bosch injectors have a screen or basket in there at the top, but the Accel may be constructed different? Regardless, it looks like replacing injectors is justified (as is the expense) and you'll be pleased with the Bosch.

The oil film might be leakage from the PCV system. Those passages carbon up pretty bad, pretty quick but don;t really create a problem,. Just messy inside. From your photos your intake is not very dirty at all.

I've seen lots that had crud caked in the corners and crevices.

 

[joshwilson3]

Interesting...the spring. I have no idea what that is ! Could it be from the pintle of the injector? the pintle return spring? I know the Bosch injectors have a screen or basket in there at the top, but the Accel may be constructed different? Regardless, it looks like replacing injectors is justified (as is the expense) and you'll be pleased with the Bosch.

The oil film might be leakage from the PCV system. Those passages carbon up pretty bad, pretty quick but don;t really create a problem,. Just messy inside. From your photos your intake is not very dirty at all.

I've seen lots that had crud caked in the corners and crevices.

The reason it is so clean is because I cleaned the engine last year. There was a ton of caked in crud all around the intake.

I think the puddle of oil at the rear of the intake is probably the intake bolt. I'm gonna go around and check the torque on all the bolts before I do any bolt pulling.

 

[TedC]

Which cylinder had the bad injector? How did that spark plug look like compared to the others? I would take apart one of the other Accel injectors and see if they use a similar spring inside. Would be great if you uncovered the source of your high RPM condition due to a defective injector.

 

[joshwilson3]

Which cylinder had the bad injector? How did that spark plug look like compared to the others? I would take apart one of the other Accel injectors and see if they use a similar spring inside. Would be great if you uncovered the source of your high RPM condition due to a defective injector.

It looks like #8.

 

[boomdriver]

Which cylinder had the bad injector? How did that spark plug look like compared to the others? I would take apart one of the other Accel injectors and see if they use a similar spring inside. Would be great if you uncovered the source of your high RPM condition due to a defective injector.

Do you know if there is a pintle return spring that the injector uses to keep closed until the pulse? I know that most fluid control systems do have some sort of tension on valves or needles to keep them either open or closed, depending on the design intent. I was unsure if a spring would be fast enough for a fuel injector, or if the injector was completely managed by the coil/pulse. Interesting that the spring could find its way up to the top. That would mean that some form of retainer was broken and possibly in the rail or trapped in another injector.

Would be great if this solved the RPM spike.

 

[TedC]

Image of a typical injector. Looks like a similar spring. Doesn't the spring keep the pintle closed for safety reasons. Otherwise, they could remain open if power was cut off. I would suggest taking apart one of the working injectors to determine if any other parts are missing from the #8 injector.

 

[joshwilson3]

I've got the injectors in. I connected my fuel pressure tester. And I primed the system a few times and noticed the pressure dropping fast. I kept priming with the key to "on" every so often. And the pressure would got to 42, then drop to 30, and slowly drop from there. I've relieved the pressure with my tester a few times to try and get rid of any air.

Last I checked, the pressure would go to 42, then go straight to 38, then slowly drop from there.

I've checked several times and everything is dry. So, I don't think anything is leaking as I say I would have found something after several hours. Before I took anything apart, the pressure would go to something like 40 and hold.

Just wondering if the pressure drop may be normal since I haven't ran the car yet?

 

[aklim]

Try running it for a bit. That might burp all the air out of it.

 

[TedC]

I also think you have air in the rails. You can make up a soapy mixture just like you would to test a natural gas or propane fitting and double check all the o rings looking for bubbles. I remember having to bleed the rails about 4 times before the pressure was within specifications. FIC flow matches and tests each injector, so I doubt you have a leaking injector.

 

[joshwilson3]

I also think you have air in the rails. You can make up a soapy mixture just like you would to test a natural gas or propane fitting and double check all the o rings looking for bubbles. I remember having to bleed the rails about 4 times before the pressure was within specifications. FIC flow matches and tests each injector, so I doubt you have a leaking injector.

I was thinking probably air in there since I primed several times over a 2+ hour period and still couldn't find any leaks.

I could probably try the soap test.

Only problem I had putting the rail together. Is I got the tube in the FPR, but the other part of the FPR didn't line up with the rail. So I had to mess with it and I think it started off going in at an angle. But I held the FPR flush with the rail while I put in the bottom bolt. Though I'll probably spray that crack with simple green to see if it bubbles.

 

[boomdriver]

its just air in the system. Air compresses behind the fluid pressure and will show your full pressure, until the source (pump) is discontinued then as the air expands again to normal atmospheric pressure (1 bar) then the gauge drops slowly as this happens. Rest assured there is gas and pressure present, so any leak would have appeared. Running for 5 seconds will finish removing any air.

The FPR...not sure without seeing what you;re refering to. It should go back together exactly as it came apart. Make certain that something is not in backwards or turned around before finishing the assembly.

 

[joshwilson3]

its just air in the system. Air compresses behind the fluid pressure and will show your full pressure, until the source (pump) is discontinued then as the air expands again to normal atmospheric pressure (1 bar) then the gauge drops slowly as this happens. Rest assured there is gas and pressure present, so any leak would have appeared. Running for 5 seconds will finish removing any air.

The FPR...not sure without seeing what you;re refering to. It should go back together exactly as it came apart. Make certain that something is not in backwards or turned around before finishing the assembly.

Thanks. I'll go ahead and put it back together.

When putting back together. I put the fuel pipe in the FPR first. Corvette Fever pics:

Then you have to put the part sticking out of the FPR into the rail:

That little piece didn't line up with the hole in the rail as I guess the pipe moved it out of alignment. Though I got it in there and bolted down.

 

[boomdriver]

Thanks. I'll go ahead and put it back together.

When putting back together. I put the fuel pipe in the FPR first. Corvette Fever pics:

Then you have to put the part sticking out of the FPR into the rail:

That little piece didn't line up with the hole in the rail as I guess the pipe moved it out of alignment. Though I got it in there and bolted down.

OoooooK......I got it now.
No worries.The pipe or tube often fits perfectly one way and not the other.

 

[joshwilson3]

OoooooK......I got it now.
No worries.The pipe or tube often fits perfectly one way and not the other.

The only o-ring I wasn't able to replace was the o-ring on the inside of that small pipe in the FPR. I wasn't able to get the pipe out, so I just replaced the outside one that you can see in the pic.

After I get it running and everything checks out. I'm going to put some GM top end cleaner through the booster supply line to help clean up the carbon from running rich. And change the oil.

 

[aklim]

Just change the plugs if you feel they are too fouled out. I don't think there is that much carbon in the cylinders from a short time.

 

[joshwilson3]

Just change the plugs if you feel they are too fouled out. I don't think there is that much carbon in the cylinders from a short time.

I changed the plugs last year. I checked them several months ago, and they weren't fouled. You could see carbon on the ring of the case though. And I did noticed a brown stain on the porcelain.

I did the GM top end cleaner last year and got alot of smoke compared to my other GM car. So, I figured it wouldn't hurt to do the GM top end cleaner again before I change the oil.

 

[aklim]

I changed the plugs last year. I checked them several months ago, and they weren't fouled. You could see carbon on the ring of the case though. And I did noticed a brown stain on the porcelain.

I did the GM top end cleaner last year and got alot of smoke compared to my other GM car. So, I figured it wouldn't hurt to do the GM top end cleaner again before I change the oil.

I haven't noticed the carbon on my valves and pistons like the pictures at the gas station. I'm kinda skeptical about what exactly the effects are of the stuff. Sometimes, they just make a smoke cloud, the user feels better and life goes on.

 

[boomdriver]

The only o-ring I wasn't able to replace was the o-ring on the inside of that small pipe in the FPR. I wasn't able to get the pipe out, so I just replaced the outside one that you can see in the pic.

After I get it running and everything checks out. I'm going to put some GM top end cleaner through the booster supply line to help clean up the carbon from running rich. And change the oil.

Sounds like this car is about ready for the test drive.
If you have a fire extingusher, have it handy when you first start up and look again for any leaks. Thats only a precaution but this is a huge "if" kind of a deal.....There are at least 22 places (in this project) that could leak fuel. Better safe than sorry.

Just be careful doing the carbon cleaning so there is no worry about a "hydro'd" piston. It might be better to use one of the small vac ports so there is not a large amount of liquid entering the plenum at any one time. Get an ink refill syringe to inject the cleaner/solvent into the vac line as the motor runs. A short section of vac hose will make an adaptor between the fitting and the syringe. Some auto parts stores even sell syringes with a small tip just for this purpose.

I wish I knew where to get the fittings for fuel injection cleaning thru the test/gauge fitting on the rail. Thats how the shops do it, with a system that attaches there and runs a chemical thru the rails that gets burned as the engine runs.

I recently had a problem with rich injection that left me with a couple fouled plugs that were only weeks old. Because they were new, I just used the wire wheel in the drill to clean the plugs off. I've heard a thousand times that this creates a varnish on the plugs, but in this case the cleaning yielded instant performance. Before cleaning the idle was a bit rough, after cleaning it was smooth and steady. Those little sand blaster boxes for spark plugs are also very effective. Spark plugs don;t actually wear out very fast, if at all....they just get dirty and can usually be cleaned and re-used if there is no physical damage and the gap is ok.

 

[aklim]

I'm generally not a fan of fuel injector cleanings. You can never tell how much was cleaned and if it is flowing like it should. Every so often, take them off. It isn't that hard. Send them out to be tested. That way you KNOW it is working right and not some SOTP dyno telling you.

 

[joshwilson3]

I got the injectors in. And it looks like I'm now running lean. My BLM hangs around 145. Sometimes goes to 148.

With the key "on", my pressure was 40-41 psi and held for 20 minutes or so before falling. Which looks to be in spec of 40.5-47 psi.

With it idling, it is 34 psi. Which looks to be in spec of the 34-39 psi. I did notice when I blipped the throttle that the fuel pressure would dip some.

I'll probably redo the pressure tests. And I'll probably drive around with the gauge hooked up laying on the windshield to see what that does. There isn't any fuel coming out of the FPR.

It looks like with the 24# Accel injectors, the BLM's hung closer to 128. With the Bosch III's it mostly is around 145 all the time.