Slow to start/Low idle?

[obnoxiousblue]

Hey all, hoping someone here might be able to help shed some light on a lil buzz kill on my 1977 2.0l FI Type 4 bay window's engine.

Just recently had a head done, and the pass side exhaust manifold replaced from a rot hole in the header/broken stud. While he was in there my mechanic of several years, also replaced a fuel line that was showing some signs of dry rot.

Got the bus back, and it sounded GREAT, really quiet and powerful. I have noticed though that occasionally, without any reasonable, reproducible circumstance, I have to crank the engine longer to get it to start. It cranks with power, it doesn't sound weak, as a matter of fact, it sounds strong. It just sometimes sounds like its ready to fire, but doesn't. When its running, it runs fine, feels like it's normal self...

I too have noticed that the idle seems lower. What is the correct RPM for this engine when at idle? Im usually at about the 800 mark, but it just sounds weak there... Again, for some unforeseen reason, occasionally, the idle is closer to the 1000 mark, which sounds much healthier. I run regular fuel in it.

I dont even know where to start looking. Do you guys have any ideas on places for me to start?
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Mike
1964 Beetle
2001 Eurovan Camper

[aeromech]

I don't have any magic answers but suggest that you start by making sure your engine is tuned up with good plugs, wires, air filters, etc. Next, try to find all the grounds to the engine. Make sure that they are connected and in good shape. You should try to locate an engine wiring diagram and trace out the wiring to find all the grounds. Lastly, engine idle can be greatly affected by vacuum leaks. You might try disconnecting and plugging the vacuum line to your power brake booster just so that circuit is isolated from the system. Then see how it runs. Check the condition of all your lines, hoses, and ducting on the engine. Feel all the way around them looking for cracks or breakage. You could even try spraying something like starting fluid around the engine while it's running and listen for a change in RPM that will signify a leak found.
_________________
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