My 88 GL Wagon has some fuel system issues, and hesitates and drops in rom under load, especially when the engine is cold. I replaced the fuel filter, which seemed to help, but after I ran the car out of gas the other day it got worse again, and replacing the filter again didn't help. I replaced the spark plugs today and they are all white, powdery, and burnt,so the car is clearly running lean. Most of my experience is with carbureted engines, so I was hoping you guys had some good tips for where to start on figuring this out.

Fuel pressure check

week injector?

I'm thinking it's possible that I sucked up some gunk or dirt out of the tank when I ran it dry, and that that's impeding the fuel flow, I'll rent a pressure gauge and check it out later today. I hope it's not the fuel pump, that's the one part that's broken on my parts loyale.

Maybe your fuel injector is gunked up and dirty. Try cleaning the injector.

Are fuel system cleaners like seafoam and the like actually any good, or would I need to pull the injector and clean it outside of the car?

seafoam is a good product, cleaning the injector out of car wasnt very easy for me, so I swapped out the tb. I would also check your cts for bog out issues

Pardon my ignorance, what is the cts? I tried googling it but all I find is a million pages about Cadillacs.

Seafoam wouldn't hurt. Give it a shot! Dunno about cts above, memory fails me. Most likely some type of sensor.

coolant temp sensor. it effects your IAC (idle air control) valve and can wreak havoc on drivability. its up by the tstat

For what its worth just like to mention that this forum has been fantastic.  Newby to SPFI with my trike and you guys have helped me understand this system with your knowledge. - great!

 

Edited September 8, 201312 yr by tweety

Metered-air leak (vacuum leak or leak in the boot between MAF and throttle body)?

 

In my (limited) experience, CTS issues either throw check-engine codes (open-circuit or too much resistance) or make the engine run richer.  Typical failure mode is corroded connectors and wires.

 

Running out of gas should not make any difference regarding crud:  The tank's fuel outlet is fixed and located at a the bottom of the tank, so any crud would find itself there even with a full tank.  (Except for ping-pong balls.)

Intake manifold gasket failures are pretty common for these models. Use some WD-40 around the gasket seal while the engine is running to see if that shows a air leak up by changes in the engine speed.