5.7 GXI-A Hesitation and loss of WOT

[Lantz22]

Hi everybody! I've got a 5.7 GXI-A in a 2001 Chap and it used to run like a charm. I could hit 51-52(4800ish RPM) and now when I have low fuel and only me I can only hit 43-44(4200-4300) and If i give it full throttle she stumbles and possibly die (I haven't waited long enough to find out). Makes it pretty tough to ski and wakeboard off the boat. I've replaced all the sparks, cleaned the throttle body and flame arrestor, replaced the fuel filter, and made sure its fresh fuel. I have a hunch that it's timing but not sure??

S/N-4012042486 or 3869096 (not sure which is which)

 

[89retta]

Have you replaced the fuel pressure regulator ?

 

[Lantz22]

Have you replaced the fuel pressure regulator ?

I actually don't think I have one, if I do I cant find it on any diagram of my fuel system. I have TBI

 

[dubs283]

have you checked fuel pressure and vacuum?

when you replaced the spark plugs did you also replace cap/rotor?

did you inspect the contents of the fuel filter(s)?

 

[BRICH1260]

You mention low fuel issue, it is possible that your tank has contaminants that are clogging the fuel pick up when tank low vs filled.

 

[Lantz22]

have you checked fuel pressure and vacuum?

when you replaced the spark plugs did you also replace cap/rotor?

did you inspect the contents of the fuel filter(s)?

Checking the pressure and vacuum will be the next step. I did not replace the cap and rotor but I know the whole ignition system/fuel system was replaced less than 2 years ago, we don't get a lot of time on the boat (20 years old with 270 hours).

 

[Lantz22]

You mention low fuel issue, it is possible that your tank has contaminants that are clogging the fuel pick up when tank low vs filled.

I ran down the entire tank to its current level. I topped it off about 3 weeks ago and then ran it all the way to 1/4 or so and filled it back up. Possible issue but I feel it's the timing because of how it sounds at idle (I'm far from a mechanic but she just doesn't purrrr like a kitten.)

 

[QBhoy]

I ran down the entire tank to its current level. I topped it off about 3 weeks ago and then ran it all the way to 1/4 or so and filled it back up. Possible issue but I feel it's the timing because of how it sounds at idle (I'm far from a mechanic but she just doesn't purrrr like a kitten.)

A months wages on it being the diz cap. Almost certain of it. Standard and typical symptoms. Thee most common fault on these engines by miles and miles. Won’t be the timing. That’s controlled by ecu and won’t have moved if it ran right before.

 

[Lantz22]

A months wages on it being the diz cap. Almost certain of it. Standard and typical symptoms. Thee most common fault on these engines by miles and miles. Won’t be the timing. That’s controlled by ecu and won’t have moved if it ran right before.

I ended up cleaning the cap and rotor today. No luck on better operation. What’s your thought? Still the cap?

 

[QBhoy]

I ended up cleaning the cap and rotor today. No luck on better operation. What’s your thought? Still the cap?

When they go..they go, I’m afraid. Not sure cleaning can usually sort them. If it’s not that…it will let you down soon. That’s for sure.

 

[Lantz22]

When they go..they go, I’m afraid. Not sure cleaning can usually sort them. If it’s not that…it will let you down soon. That’s for sure.

Replaced the cap sunday, no change im afraid!