I just got my engine put back in my car after the new rods and pistons. The c/r is the stock 9.4. It is just bored 20 over. I just got 1000 miles on it and soon will be adding the turbo on. what I am wanting to know is the car running to rich or is it the timing. the problem I am having is when I start my car and let it run for like 10 min to get warm I come out side to see there is black marks on my driveway? if it is running rich why is it that rich? the other thing is at low rpms it sounds like a Diesel Engine but over 2500 rpms it sounds fine.


thanks

 

more info needed.

what year, what model, what ecu, what engine, and most importantly, more description about these black marks and exactly where they show up

 

i have a 1995 acura integra ls. and the marks are about 12 in. from the back of the car.

 

if you're running rich, your spark plugs will be fouled, and you'll probably see fuel in your exhaust pipe... the marks.. are they puddles? what do they smell like?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by love2xlr8integra &raquo;</TD></TR><TR><TD CLASS="quote">i have a 1995 acura integra ls. and the marks are about 12 in. from the back of the car.</TD></TR></TABLE>

12" from the back of the car, as in, 12" from your exhaust tip?

Is there black smoke coming out of the exhaust at any time?

What is your timing set at? If it is indeed advanced, that will cause the ECU to send more fuel. How is the fuel mileage?

When you say it sounds like a Diesel at low rpms...that almost sounds like your valves are out of adjustment.

 

"sounds like your valves are out of adjustment" yea i was thinknig that to but it was not some people told me it maybe piston slap

 

welcome to the wonderful world of piston slap. I had the exact same problem with mine, although i was changing compression ratios altogether, goin from all motor to 9:1. Id put 200 bucks that in two weeks, it will not be running rich anymore, give it some time to rethink everything and get the bugs worked out, that will be fine and dandy.
As far as the diesel sound, unless its a light ticking (which sounds nothing like a diesel) its piston slap. I installed my new forged pistons about 2500 miles ago with an overbore on stock sleeves. I get that diesel sound at idle, but after i start accelerating, it blends in and goes away. Theres really nothing to do about that, unless u plan to rebuild again. When this happened to me i researched that alot, and found alot of people with it that have motors that have taken alot and gone along way. Just pray, thats what i do.
Also, if u did not touch the head at all (like i didnt do either) and the sound at idle is louder now than before, then u know its not the valve adjustment, its slap for sure.
Good luck
Dan

 

dose the slap hurt things at all, and i have 1,000 some miles on it now the ecu should have releand itself by now right. i thought that only take 20 min to do.

 

nah it took mine over two weeks, if u r still running real rich after that long then its time to tune, either cheap with VAFC or otherwise. The slap, in long term, will hurt yes. There are no positive sides to having slap, its basically the piston moving around, which is not good. however some motors, depending on how extreme the slap is, will last along time. im hoping mine is one of them.

 

yea i am going to get it tuned with my turbo so only about one week more i have a hondata s200with boost but i am waiting to put it on till i put the turbo on