So I was just doing a cruise like I normally do before heading home and I was coming to a stop and noticed my idle sounded different, like a v8 with a big cam. So I drive more and come to a stop and it's louder and shakes the car. It's like the same feeling and sound as when you pull the choke and get too much fuel. So I'm immediately worried and drive home fast and the sound and shaking gets worse the faster I go. I checked my oil pressure no drop at all, checked my oil, it's where it's suppose to be, checked for leaks, nothing. Just recently did my spark plugs so it can't be that. But it's weird how it went from randomly smooth to sounding and shaking like a v8. It's like my engine has just randomly started getting too much fuel but I know it's not because nothing has changed. Can anybody help me out?

 

power loss? not firing on one rotor..
no power loss? exhaust leak..? vac leak? vacuum advance fail?

 

I have exhaust leaks, but I don't see how any of the others could happen.

If it misfired, wouldn't oil pressure drop? Mine hasn't changed at all. Always right below 60 lbs.

 

Check compression. Check condition of spark plugs and ignitors. Check condition of float needles. Check for clogs in your return line and charcoal canister lines. Check flow rate of your fuel pump.

 

no, a mis fire doesn't effect oil pressure, only rpm effects oil pressure., a miss can cause rpm at idle to be lower if it idles at all...

 

It will idle at 800 rpm starting cold, then at 1,000 rpm at operating temperature as of 20 minutes ago. The exhaust makes a small burping noise, like the sound of too much fuel, and my fuel filter under the hood is full of fuel when it usually is only 1/2 way full and you use to be able to watch it flow. I have to start getting ready for work in 30 minutes, and I won't be able to really start taking things apart and checking them until Wednesday. The only reason why it really bothers me of how it just randomly started happening.

 

I'm going to get ready early and pull my plugs and check those out first before I go to work. I'll get back with you guys in about a hour.

 

If the fuel filter fills up all the way your needles are flowing too much fuel into the bowls. Tap the banjo bolts on the fuel rail lightly with a hammer to jiggle them loose while idling and revving.

 

I'm not familiar with those words haha I'm carbureted, where is this exactly located?

 

I didn't pull my plugs but I did fiddle around with my mixture screw, and that didn't change a thing. I did make a video for you guys so I'll figure out how to upload this and see if that'll help.

 

Here's the video I made.

 

Tap the two larger bolts holding the fuel supply tubing to the carb. At 10 o clock and 2 o clock.

 

The rythmic misfire could be a stuck side seal. Or it could be brapping from being too rich. Where are the fuel levels in the site glasses? You know the little windows where one is difficult to see without a mirror on a telescoping rod. My guess is it's in the middle and tapping on the banjo bolts won't do any good.

At worst I think you broke an apex seal. Did you take the spark plugs out and listen for three even pulses per side?

 

My choke cable is perfect and could a large exhaust leak cause the engine to shake from back pressure?

 

the exhaust leak could account for the increase in idle. poor mixture could cause it to shake.

 

This is a pain in the ***. I have a mechanics stethoscope at the shop and I'll use that to see if there is scraping inside the engine Wednesday, when I get out of work I'll pull the plugs and tap those banjo bolts tonight.

 

Tapping the bolts soft then hard didn't change anything now time to check the plugs.

 

Checked spark plugs they are all good and igniting. Just my engine is randomly getting too much fuel.

 

I've never worked on a carburetor until I got this car and turning the mixture screw doesn't seem like its doing any thing either way I turn it. Now my garage smells like a gas station and I'm still scratching my head wondering why it's getting so much fuel. I have to drive to school in the morning though and I have a few hours after school to work on it before I go back to work. How would I be able to check the float and fix it if it is the float I'm reading my manual and it has no reference to that.

 

I'm wondering if you should fix the exhaust leak first? Maybe it is amplifying something that isn't an issue..

 

That's what I was thinking, but spending money on exhaust and not fixing the problem would suck. I can get my car on the hoist Wednesday and ill find how big the leak is. It's big enough to leave rusty water (condensation from the exhaust and rust from the hole in the exhaust) on the ground when idling for a while.

 

I checked foxed.ca and all the troubleshooting of too much fuel has to do with the needle valves and floats. My fuel pump is good for sure and not running too much pressure. But coming to a stop at a stop sign shouldn't all the sudden mess with the fuel flow rate of my carb.

 

I've been reading about back pressure and it really is sounding like that is the issue. Back pressure leads to insufficient combustion (maybe that's why I think it's running rich).

 

Exhaust leak wont cause a poor running engine. Ive driven rotaries with open header that performed just fine other than non functional 6 ports. You may get a little popping noise from fresh oxygen entering the hot exhaust pipe. Your looking for an internal carburetor problem most likely related to the floats or needles. Just because the sight glass reads half way doesnt mean the floats not out of whack. A sticky needle will cause some troubles too.

 

It could also be poor manifold vacuum signal from a bad TB gasket or throttle shaft.