i just bought an 88 crx si, and its running rich...it spews thick black smoke constantly..and i cant figure out why. i just changed the o2 sensor because thats what everyone ive talked to said it probaly was, but it didnt make any improvement. i'm getting no codes. it smokes the worst at idle.the car has 165k miles..not sure if that matters..but i figured someone might ask.. anyone have any ideas?

 

Since your blowing alot of smoke out of the tail pipe, chances are that you need a new head gasket or even worse, you may need to replace a (few) piston ring(s). As for running rich, my guess that would be the head gasket.

Any other suudestions out there???

 

anyone else??????

 

Headgasket , if its ever black or a watery white substance that has a substantial amount coming out and isnt just condensation you prob. need a new headgasket, not hard at all. a Haynes willl tell you exactly how to do it.

Now see like in my case my rex has 202,000 miles and when I get on it and and shift I get a nice big cloud of blue smoke.....aaaawww thats teh worst at this point checked my compression and it was stellar so my comp. rings are okay its just my oil rings and about every 2000 miles I add 2 more quarts of oil, then I Just change it around 2500 2800, and I use regular motor oil not synthetic becuase its thicker and stays on the cylinder walls alot better then synthetic will in my car syn will burn to fast with my bad oil rings.

Only way to fix rings is to pull engine out and totally dismantle it, I suppose you could go from the ground take out oil pan(messy) remove rods/bearings(messy and somtimes painful ...lol) and manually pull out the piston, replace rings and be bacck on the road.

 

I have a few observations. First, you said it was black smoke. Not white or blue smoke. If this is the case that would point to a rich running car. It is possible that you could be burning oil as well. Is the car using oil at all? Second, burning oil could be the result of either bad rings or valve seals. Both of which can be rather pricey. Finally, as far as the headgasket, if that were a problem you would probably notice overheating, oily coolant, and even some performance issues. When my head gasket went I noticed that the car stumbled around 2500 rpm. You may want to spring for a compression test. That would give you a pretty good idea as to whether or not there is a internal (seal, rings, head gasket) problem though it won't identify which.

It is not possible to pull the pistons from the bottom. They have to come out the top.

I hope this helps.

 

It's probably your Fuel Pressure Regualator. Have it checked out to see if it's operating at the corret pressures...

Then comes cam alignment and timming, and the vacuum line too the MAP sensor if it has one, for cracks, fitmit, etc...

White smoke can either be a blown head gasket, or running a little too rich....


[Modified by 88_SC_CRX_Si, 6:33 AM 6/11/2002]

 

you can take them out from the bottom but when you put them back in you HAVE to put them in from the top because of a ring compressor.. but most people take them out thru the bottom

 

I pulled a crank about a month ago and the piston would not drop out through the bottom of the block. There is a lip on the bottom side of the block that will not let the piston pass through. D16A6 if anyone cares.

 

to pull them out the bottom you need to pull off the tranny, pull the flywheel,pull the crank and crank pully.

 

I did all of that, still no dice.

 

ok...the smoke is not white..grey..or anything like that...the car runs fine...plenty of power...its BLACK smoke..thick black smoke. its nauseating ..because it smokes mostly when im sitting still idling..so when i come to a stop i smell it..it makes me sick..i can't really even drive the car..so anyway..i'm pretty sure its a fuel problem..not an oil or coolant problem..the car always operates at normal temp..so.maybe fpr? or injector? i tried setting the timing but for some reason the timing cover is right up against the crank pulley..so the pulley has worn part of it away..and i looked all around the pulley and i didnt see any marks at all to set the timing...so i cant even set the timing..not that i really think this would make the car run THAT rich...anyway let me know what you guys think..thanks

-corey

 

*** just re-read original post and noticed the idle part. I guess the below doesn't apply, but I'll leave it for future ref.

I had this problem for years. It was mostly at WOT, but it was really really bad. I took it to the H garage, and they couldn't figure it out. They were stumped. Finally I swapped the motor and took the old motor apart. It ended up that there were such horrible carbon deposites and fried oil stuck to the tops of the valves that the motor couldn't get enough air. Since at WOT the car is in look it was getting tons of fuel but not much air. I've since heard of this or witnessed this on about 4 other D16s (pretty much every one that I know that still runs a D16).

When I say that the valves had deposites, I'm talking to the extent that they wouldn't close all of the way in to the seats, and they weren't shaped like valves anymore. It was unreal.

I'll bet if you send the head out for a normal cheapo rebuild ($200) your problems will be solved. Like I said, I've seen it on a bunch of motors over the years, and it always seems to be the cause of the black specks on the rear and the black smoke.

I might be wrong, but its something to think about.



[Modified by therealciviczc, 8:38 PM 6/11/2002]

 

black smoke:

burning oil check rings seals etc gaskets etc
fuct up o2 sensor
fuct up cat