So my idle has been bogging now for quite sometime. Whenever I am in gear and I'm at a stop light and have the brakes applied. Its seems like the cars wants to die on me but doesn't. The idle will drop between 200 - 300 rpms and will have some hesitation/vibration. It does have almost 200k on it now, so maybe it could be fuel related? but i'm not sure. What I have replaced is the spark plugs, spark plug wires, distributor, ignition coil, TPS sensor, cleaned the IACV, and replaced the throttle body gasket. Also the timing belt was replaced recently along with the camshaft positioning sensor. If anyone can help me out with this and what might be causing it, that would be awesome!

 

How does the car drive? When you are going is there a lack of power or bucking or any other symptoms? Is the only problem is the idle it could be as simple as cleaning the throttle plate or a clogged pcv valve. Depends if there are other problems or not.

 

Just a guess, but what about a bad vacuum line going to your brake booster, or a leaking booster? It would be noticeable at idle, but not at highre RPM's. Good luck, T

 

sounds like rings...check compression

had same problem as you.

 

It drives good, but it does seem like there is a lack of power when accelerating on the highway. Also, my gas mileage hasn't been as good either. Would a thicker oil help offset this compression loss until I get the rings replaced? I have been running 5w-20 currently. I have cleaned the whole throttle body twice, replaced the throttle body gasket and the PCV valve. The brake booster doesn't seem to be leaking. If it was to leak wouldn't it make the idle higher? if there was a vacuum leak I mean. I have not checked the rings or compression, but what would be the signs of bad rings? wouldn't I have blue smoke coming out of the exhaust to?

 

My b16 was turbo'd and i would only notice a loss of power in boost, regular driving seemed fine.

Thicker oil isnt gonna really help the issue. If it was a vacuum leak, more than likely you would be experiencing a high idle or a high fluctuating idle. Go ahead and do a compression test and see what the numbers say. I think you can rent one from autozone, althoug i picked up one off of ebay for about 50 bucks that works well.

Start by testing, guessing the issue wont get you anywhere but confused

 

I will go ahead and do a compression test when I get some free time, but I do want to mention that my car isn't burning oil, wouldn't it be burning oil to if my rings are gone? or is there separate oil rings? Also when I have my headlights on and stop at a stoplight it does idle fine. Do you think it could be my IACV malfunctioning? I know they seem to cause quite some trouble in these engines.

 

Alright So I did a Compression test on all four cylinders. These are the readings (Highest I Obtained):

Cylinder #1 110PSI
Cylinder#2 100PSI
Cylinder#3 95PSI
Cylinder #4 110PSI

So I think you are right, I either need new piston rings, or a new head gasket...

 

try rings, headgasket would be if you tried a leakdown test with bad results

 

Yea, I am gonna get one of those done to pin point what actually is gone. Can you recommend anything to raise compression til I get some money to get the work done? Thicker oil, Restore, Seafoam??