I have some hesitation when I accelerate, especially when it's wet out. My plugs & wires & cap are new within the last 4 or 5 months, and my fuel filter is new within the last 2. Is there something that usually causes this or could it be a million things? I also get terrible gas mileage in town, but great on the highway ( more of a difference between the two than I'd expect ) and in general not much power.

'87 GL Wagon, carbed. If you got any ideas, thanks!

coil? vacuum lines? is the carb sticking?

coil? vacuum lines? is the carb sticking?

 

Not sure not sure and not sure....I've checked all the hoses around the carb/air filter and all are connected, and I've sprayed the carb with cleaner. Haven't checked the coil..

How heavy footed are you around town? When I was drove it with my foot buried, my gas mileage was about 15 mpg. Now I have settled down(and a lot more highway driving) and I get 30 mpg. If you stay out of the secondaries, it helps a lot with mileage. The hesitation is probably just the carb being clogged and if spraying it didn't help, run some Seafoam through the gas, and if that doesn't help, I think you might need a carb rebuild. At least, that's what I would believe.

Well...sometimes just to get it to move I've got to be a bit heavy footed, but I'm not a racecar driver around town at all, I accelerate from stops at a reasonable speed. I'll try seafoam, thanks.

Timing could be off some.

Cat could be getting plugged.

Just to dummy proof your responses for me: we're talking ingnition COIL and CATalytic converter, right?

How recent was your air filter change? I'd have to agree with the thought of a clogging catalytic convertor. One way to find out. Pull the exhaust down just ahead of the convertor. Go for a short spin and see how it runs unplugged. If it's a noticable difference change the convertor. Remember this is very loud so don't go by sound. Cheers. Dave.

Air filter was maybe 6 months ago. I could try that.

it could be ignition timing as well, if its been a while since its been done...it could have retarded itself. and on that not it could verry likely be the distributor vacuum advance

Ok with all these possible culprits, how do I check them? No idea where the distributer vacuum advance is...retarded timing I may be able to do something with...

to check timing you unfortunately need a timing light, if you have one great...by the sounds of it though...you don't.

 

to check the vacuum advance is easy. with the engine warm and running, remove the vacuum line from the distributor. if you hear a change in the idle its working, if you don't it isn't.

Hesitation might also be a cracked cap, since you say that it happens more when it is wet out. moisture may be building up inside the cap and causing this even though it is new this stuff can happen.

Alright, thanks everyone. I'll check this stuff out this weekend.

Removing the vacuum advance line is likely to cause a change in the idle due to the vacuum leak, more than the change in effect on the timing.

 

A better way is to pull the advance hose with the engine shut off, and suck on the end of it. Watch the distributor to see if it moves when you do. Plug the end of the hose with your tongue, and see if it holds vacuum. Tastes bad, but it works.

 

I don't expect it is vacuum advance. If it was bad, he would be getting poor mileage on the highway, which is when the vacuum advance kicks in. Most cars use ported vacuum, which does not affect the timing at idle.