TireSmoke.org

I had the fuel pressure gauge all along. I did get to see 'Smoke this evening as he
used the excuse of returning the compress gauge for a joy ride in his sweet Vette.

I got a tip from Paul Carson that the knock sensor might be picking up the noise from the lifter and pulling all sorts of timing out of the car. So we pulled the plug and drove it, but to no avail, it still is pretty down on power under load, but feels OK under normal light driving conditions. We pulled the valve cover off the driver's side since that's where the noise is coming from, but everybody is in tact and going up and down as designed, at least under starting cranking speeds. No broken springs, rockers, etc. So the lifter has to be really sticking in the hole, or collapsing enough that the valve isn't opening or closing as designed under load.
While we had the valve cover off, we (basically) tested all the resistance for each coil and made sure the ICM is putting power out as designed and all seemed OK there. We cleaned off all the grounding areas, and fixed a missing coil bolt, and correctly mounted the engine lifting lug while we were in there too. But none of that helped our problem either.
So at this point we're deciding to either do it ourselves or wait a few weeks for Paul Carson to do it. It's not a terrible job, but it's a little tight in there and pretty cramped, and for $350 (labor) it just might not be worth the back ache.

-BP

could you be short on fuel pressure? Not being there to drive it I can't tell what it's doing but we have not confirmed fuel pressure under load. Its a long shot but could be partially blocked fuel filter, fuel pickup, bad fuel pressure regulator? Either way the lifter is ticking and needs fixed.

We haven't driven it with the fuel pressure gauge on it but we checked it at idle and it's where it should be (don't remember how much now). And it has a new fuel filter.
Like you said, it needs this either way, and I don't want to throw parts at it. Fixing the lifter will cure that, eliminate it as a problem, and fix our oil leak. If it doesn't cure the running condition, we'll keep going.

-BP

TrackBird is back home with new lifters and no oil leaks.

Same ticking noise and lack of power persists.

Hmmm?

I didn't see any mention of exploring a fuel injector solenoid as the source of the ticking and possibly the loss of power.

After another discussion with Paul Carson last night, he's pretty confident that there are two different problems going on. The lack of power is most likely a dying fuel pump. It will hold pressure under low power scenarios, but as soon as it's asked to do real work, there's not enough flow to maintain pressure, so we'll recheck the fuel readings under load and we should be able to sort that out quickly. And since the sending unit doesn't work correctly, we'll most likely replace everything in the tank since we'll be in there.

To the ticking... We've been using 10w30 oil in this car where it calls for 5w30. I did notice that it was quieter when we got it back to dad's place than when I started it cold at Paul's shop. Still a little noisy, but different. He suggests going back to 5w30, or if we're worried about the excessive heat from track days, going to a 5w40, so it's thicker when it's not, not when it's cold.

The u-joint we replaced with a used one isn't cutting it, as it was creaking when I got the car back too, so that will have to be replaced with a new one.

Hopefully we'll get this thing all fixed up just in time for winter.

-BP

as far as lack of power, I have a some guesses

1) knock sensor. in the Saturn when this failed the ECU would not advance the timing which cost power. make sure you know what the ECU does with no signal if you test this by disconnecting it.

2) fuel pump - bad ground. I know a guy who had a problem with this recently where the pump lost power due to inadequate grounding for the fuel pump circuit

3) ignition. bad grounds

4) As Fred32v suggested - bad TPS

5) has the fuel filter been replaced?

6) fuel pressure regulator

as far as the ticking:

1) are these the right length pushrods (long shot). in Rachel's hemi the way to adjust lifters is by changing length of pushrods. If I understand correctly this is a Jasper engine and I don't know if they would have done something here to make more power. With just a little bit of wear, or little drop in oil pressure, perhaps one is just a bit loose

2) rocker arm stud too long/not installed all the way (long shot). Again rebuilt engine with unknown motives accompanied by very slight drop in oil pressure

1- We've already checked it without the knock sensor, same same.

2- Maybe bad ground, maybe bad pump. I'm still leaning toward bad pump as the car has 180k miles and I ran it dry several times during the last track day, and this is when the problem started to rear its head.

3- Already checked good

4- We can check this with my scan tool.

5- Yes, done.

6- Possible, but has good pressure at idle and low rpms

Ticking stuff

1- It ran fine for a year, so I don't believe it has anything to do with that. Oil pressure still really good. Jasper is basically a stock engine rebuilder, so I doubt any funny stuff.

2- Paul inspected all the valvetrain and looked good when it was apart.


We'll try the stuff we mentioned earlier as they have high probability based on past experience and go from there. It turns out I have a fuel pump from the S-10 that should work. I know I put a high volume one in the S10 from a Gen 4 F-body, so it should be the same and is also higher output.

-BP

forgot it was run dry a couple times. seems quite plausible. just throwing a bunch of ideas out there as food for thought since gas tank drop kind of a pain

Absolutely. I may consider cutting the floor if that's possible in this car and pulling it is a PIA. I haven't looked into it yet.

-BP

I'm thinking the time to cut the floor is when the tank is out in order to avoid cutting or drilling into something by accident. I assume there is no reason to leave space between the tank and the floor. Not sure what your plans are in this area

Seems that GM finally got their crap together in 1999 and put a plastic tank in these cars with a bucket around the fuel pump assy. This solves a lot of problems, but I have to do more research to see about V6 swaps. I think a new V6 sending unit and pump will get it in the car and make gas go to the engine, but probably will still have fuel level issues.

https://ls1tech.com/forums/fueling-inje ... te-up.html

-BP

Today we drove the car with the fuel pressure gauge attached. Unfortunately and fortunately it has 45psi at idle and light driving, and 50psi under load. It never falls off. So we don't need a fuel pump.
We checked the codes again and got a TPS code. Hoping for the best, we put a new TPS sensor in, but it did not fix our issue. Looking for other issues we pulled the nasty dirty air filters and started cleaning them, and also pulled the screen and the MAF sensor for a quick cleaning. Although the car feels a little better, it's still not right under load. We have more ways to test the MAF sensor and will do that next time. I'm hoping this is our problem, but new ones are over $100 so I'd like to be sure before I buy it. I hate throwing parts at this thing...

-BP

Since we needed a new u-joint in the rear, I bought another used aluminum driveshaft and new u-joints all on eBay. I had Paul Carson do the u-joint swap to make sure we weren't missing something and those got installed on Monday. Taking his advice, we switched back to 5w30 from 10w30 to help with the ticking problem too. We didn't really have time to drive it and do real diagnostics, so we didn't. I did hook up my scanner to see at least that the TPS, Timing, and MAF sensors are all reading something and moving with engine RPMS. Now to figure out what they should be at before the next test drive.

-BP