2000 GTi - Doesn't Run Right After 20 Minutes

[Jbrad]

Does anyone have any ideas about what to check on this:

2000 GTi, starts and runs perfectly for the first 20-30 minutes, but then - after getting good and hot and running a while - it wants to idle rough and die and then is also very difficult to start.

*Changed plugs, didn't help. Cleaned fuel filter, didn't help (Wasn't dirty).

*Carb looks OK, but hasn't been removed and cleaned/rebuilt. Figure the carb would affect it when it's cold if it was the problem.

*Pulled the plugs when it is acting up and they are pretty dry, definitely not saturated with oil/gas. Good spark when cranking.

*Acts the same way whether fuel selector is in Run or Reserve position.

Thanks to everyone in advance for helping with ideas on this one.

J Brad

 

[Bills86e]

Described condition sounds like lean, from clogging lines, carbs.

 

[Jbrad]

Bill:

Thanks for the reply. I agree, it does sound like lean - except that it runs so well at first. Also idles perfectly cold, but doesn't want to idle hot (wants to die hot)...

Brad

 

[my787]

you can also look at your spark plugs and check for a lean condition. It is somewhat simple to take the carbs off and rebuild/clean them.

 

[Bills86e]

An air leak may get worse as the motor warms up. Try removeing the air-box when
warmed up and lightly spray carb cleaner around the case joints, intake gaskets,
& RV cover to find it. If air is leaking in, the spray will make the engine RPM rise,
and you've found your leak. Check the supply line, separator filter cup-cap and its
O-ring. It can crack from over tightening. If you open gas cap and get a large sssss
the vent line (s) may be clogged. Those two have one-way valves that should open at 3-5 psi. Bills86e