The car smells of unburnt fuel bad at idle. So bad it either gives me headaches, or people around my car complain.

High idle going from 1000 to as high as 1700, but usually sits at about 1500 on average. No visible leaks, and I've sprayed everything to check the mani with no stumble.

I had the car scanned this afternoon and I wrote down a few things (1000rpm idle):
Target idle 850
IAC counts were 52
BLM - 5 and stuck there, even when revving. It went to 16 a few times, but after five min it never moved from 5
O2 Bank 1 - Low as 45, tracing up to as high as 660
O2 Bank 2 - Low as 430, tracing to as high as 820
MAF - 12 g/s averaging about 9
MAP - .7V

Long Term Fuel Trims
Bank One -1 to -5.5
Bank Two 2 to -8.6

Short Term Fuel Trims
Bank One -1.6 to 0.1
Bank Two -3.1 to -1

Timing +25 to +35

No Knock counts, no misfire All injector PW looked good.


The tech was at a loss and had no ideas, but the car stinks to high heaven.

I average about 10-12mpg mixed highway but mainly stop and go driving. I went on a trip and the mileage went to 15 if that.

Anyone have any ideas? The O2's are bosch, and when I bought the car it was running so rich it wouldn;t idle (crossed plug wires, fouled plugs) Could the O2's be going?

 

sure sounds like a vacuum leak or a bad iac

do you have a cam in there?

 

CC305 with 1.6 rockers

 

Tuned?

 

According to the previous owner it was Dyno tuned.

I pulled 2 codes from it earlier as well.

EVAP Purge solenoid - disconnected because the previous owner blocked it all off.
MAF Circuit values out of range or something like that (I think it was me disconnecting the MAF while it was running)

 

there is your fuel smell, with no purge valve pressure is building in the gas tank and bleeding off anyway it can, and what is bleeding off is fuel vapors, hence your smell.. not to mention if it was tuned for the cam they usually throw some extra fuel in at idle to make it idle better

 

I just went out there and decided to do the spray test on my wires.
3,5,4,8 are all arcing from the boot to the hex on the spark plug.

Damn Taylor wires.


I'll try and rebuild the EVAP system this weekend, is there somewhere with a diagram I can reference? He just removed the lines and left the solenoids etc there.

 

check shoeboxs site

but that does not explain your high idle situation, i would check again for a vacuum leak, and also check your intake elbow for holes and the bottom where it meets the throttle body to make sure it is not rolled over

 

I have a WS6 RAM AIR.
The tech at the shop checked around the TB for leaks and couldn't find anything. Its hard to hear anything with the filter right there sucking air.

They have a smoke machine they hook up to test for leaks, but we ran out of time. I'll see if he can do it for me this weekend.

 

Wouldn't the IAC counts be lower if there were a leak though?

 

The car smells of unburnt fuel bad at idle.

You have an ORY = no cats. Its going to smell of fuel without cats. That's what they are there for.

Who tuned it? Is it possible the valves are adjusted too tight, increasing overlap, and hence the fuel that blows through the open exhaust valve at idle? The 305 shouldn't be big enough to cause a problem like that.

High idle going from 1000 to as high as 1700, but usually sits at about 1500 on average. No visible leaks, and I've sprayed everything to check the mani with no stumble.
Target idle 850
IAC counts were 52

Something wrong here.... if its idling above the target, the IAC should be closing down to bring it back to spec. Doesn't sound like a vacuum leak.

But then there's this:

BLM - 5 and stuck there, even when revving. It went to 16 a few times, but after five min it never moved from 5

I don't think you meant what you typed.... a "BLM" is a long term fuel correction. I think what you meant to type is "BLM Cell". If that's the case, there is something preventing the PCM from idling in Cell 16 like its supposed to be. What it the TPS voltage? Is it below 0.90V? Does the speedo work correctly.... looking for a problem with the VSS?

When the PCM thinks the throttle is still open, or if it thinks the vehicle is moving, it raises the idle speed.

O2 Bank 1 - Low as 45, tracing up to as high as 660
O2 Bank 2 - Low as 430, tracing to as high as 820

Both O2 sensors should be moving rapidly back and forth over the full range of 0xx - 9xx mV. Problem with trying to take data off a scanner is that the O2 readings are changing faster than the scanner can display them - about 9 times per second. Writing down scan readings for O2 sensors is close to useless, if they are cyccling like they are supposed to be.

MAF - 12 g/s averaging about 9

Higher than it should be, but that's because of the elevated idle.

MAP - .7V

I have to check my reference, but I think this would indicate a MAP of less than 30kPa. That would seem to be a bit on the low side, and may be an error. That would represent a vacuum exceeding 21"Hg, which is not indicative of a vaccum leak. Is it possible your reading was not .7V, but rather 70kPa?

Long Term Fuel Trims
Bank One -1 to -5.5
Bank Two 2 to -8.6

The PCM is pulling out a bit of fuel in response to the O2 sensors reporting a slightly rich condition.

Short Term Fuel Trims
Bank One -1.6 to 0.1
Bank Two -3.1 to -1

Not really usefull.... these should be changing rapidly, in response to the O2 sensor feedback.

Timing +25 to +35

High for idle, but probably reflects the excessive idle speed.

The O2's are bosch

A lot of people have reported problems with the Bosch O2 sensors on the LT1. Most people recommend/prefer OEM AC/Delco units.

 

The TPS voltage I did not look at, but when it was idling at 1000rpm, it was at 0% and after about 4 min and the idle went up, it was at 2%

We noticed once when I revved the engine to 3000rpm, the vehicle speed went to 10mph for a sec but never did it again after that.

I have a mechanical vac gauge and it was reading at 20in vac, but the scanner was reading 14-15in

I'm working from home today, so I can drive up to his shop again and bum his scanner for a few if I need to. I'll see if I can get better readings for the TPS voltage and speed.

 

alright-

on the way there the car was missing a little, SES came on and I pulled codes with the scanner

p0100a MAF FREQ INSUF VARIATION

Cleared it out and let it run, came back up again.

IAC was at 76cnt
TPS was .59v
MAP was .9v
MAF was 2 g/s after the code





Bad MAF?

 

I reset the PCM , and reseated the MAF harness (has an extension which I assume is stock for the Ram Air?)

No codes
I reran the lines for the EVAP Solenoid, not sure if that will clear anything until I drive it around some?

I sprayed EVERYTHING and no stumble or hint of it. Yet still idles at 1k and as smooth as it can probably get with the cam I guess. Never had the car with a stock cam.

 

still no codes,

I took apart and cleaned the TB, IAC. Not much in there, but there was no change. Idle doesn't stick to 1500 like it did before, but idles at 1000-1100rpm

I picked up some new Autolite 106 plugs and will regap those to 35-40

The P106'S I have now are gapped to 50