Recorded at idle, likes stall when rolling to a stop, cuts out when cruising, 63 psi at idle on the rail. Now smoking badly during accel.....

Control Module
$10 SAE J1850 VPW
Live Data
------------------
DTC_CNT 0
FUELSYS1 CL
FUELSYS2 CL
LOAD_PCT(%) 2.7
ETC(°F) 149
SHRTFT1(%) 1.6
LONGFT1(%) 18.0
SHRTFT2(%) 0.8
LONGFT2(%) 19.5
MAP(inHg) 15.9
RPM(/min) 716
VSS(mph) 0
SPARKADV(°) 15
IAT(°F) 93
MAF(lb/min) 1.185
TP(%) 13.3
O2S B1S12--B2S12--
O2B1S1(V) 0.815
SHRTFTB1S1(%) -0.8
O2B1S2(V) 0.445
O2B2S1(V) 0.730
SHRTFTB2S1(%) 1.6
O2B2S2(V) 0.440
OBD OBD2
------------------
DTC_CNT 0
FUELSYS1 CL
FUELSYS2 CL
LOAD_PCT(%) 3.1
ETC(°F) 149
SHRTFT1(%) 0.0
LONGFT1(%) 18.0
SHRTFT2(%) 0.8
LONGFT2(%) 19.5
MAP(inHg) 15.9
RPM(/min) 720
VSS(mph) 0
SPARKADV(°) 16
IAT(°F) 93
MAF(lb/min) 1.192
TP(%) 12.9
O2S B1S12--B2S12--
O2B1S1(V) 0.895
SHRTFTB1S1(%) 0.0
O2B1S2(V) 0.445
O2B2S1(V) 0.180
SHRTFTB2S1(%) 3.9
O2B2S2(V) 0.440


Thanks guys!!

 

Got your PM.

Fueling off about 20%, though that may or may not be the stall cause. Looks like it just needs some tuning.

 

The MAP reading looks low imo.

 

Needs tuned. MAP reading is OK for a cammed engine.

 

Until last week I was running a stock truck intake/rails/injectors. To help clean up the engine bay a bit I swapped to a stock LS1 intake/rails/injectors. I know I lost power doing the swap, but the LS1 intake was free and is only being used until I can afford a LS6 intake. I am running a stock '02 Z28 gas tank, stock in-tank fuel pump, and '04 Corvette filter/regulator near the rail.

I sent the PCM to get re-tuned (mail order) for the larger injectors ('00 LS1 26.x lbs). Since the swap the car doesn't idle well, even dies when coming to a stop. Driving/cruising it does okay, but before the swap everything was fine (also mail order tune).

Last Friday during the second time driving after the swap, all at once I saw a HUGE smoke cloud come from the exhaust. It was so huge I thought the car was on fire, except it wasn't black smoke, it was lighter colored (grayish). I limped it home (only a block away) and rev'd a few times, each time produced a decent amount of smoke. I have 2.5" true dual exhaust (no H or X pipe) and it seemed to come from the driver side slightly more than the passenger side. I checked for codes, there is none. I checked the oil and it isn't looking like mayo and coolant level is fine, so I doubt its a head gasket. The engine runs at 160 degrees all day.

It doesn't seem to be blue smoke, but I disconnected the PCV lines to double check its not pulling oil from the valve covers.

After that I put the car in the garage for the day.

Saturday morning I pulled a plug and its fouled, but it doesn't look oily, just flat black.

After re-installing the spark plug I started the car and got alittle smoke at startup and rev'ing, but nothing like the smoke on Friday.

Thinking it might be a fuel issue I bought a fuel pressure gauge on Saturday and I checked the fuel pressure at the rail and its 63-64 psi. Everything I've been told says its suppose to be 58 psi.

Could this be my whole issue?

 

Got your PM. Looking at the data, you long term trims are already compensating about 20%, but you are claiming it is rich. From the bad idle, smoking & drivability that you mentioned, you may have an issue with o2 sensors not reading properly & the computer artificially compensating with additional fuel. This could be due to an o2 or wiring problem, a vacuum leak in 1 or more cylinders, or an exhaust leak for starters.

Do your o2's rapidly switch at idle?
What codes are you getting?

 

Just P0135, but I have always had that code, even after changing the O2 sensor.

I don't know what you mean by 'switching' at idle....

 

it seems that thing is dumping fuel in there like it was free.. excessive fuel will cause that smoke.. but it has to be tons of it..i wouldn't drive it you till you figure it all out...

When the car is in closed loop the o2 sensors will switch back and forth.. Do you have this isssue as soon as it starts up? if so I'd say its in the tune.. as when you first start it from cold it will be in open loop and ignoring the 02 sensors..till it warms up.. the only other thing would be the vacuum leak.. but it would have to be a pretty big one to have smoke.. what happens when you make a WOT run??

I've had cars smoke like that with stuck open injectors..damn fords..

 

It hasn't moved since Friday when the large smoke cloud happened.

I haven't run it hard since for fear of breaking/hurting something.

It had occurred to me that the injectors might be stuck open, especially since it won't hold pressure in the rails very long after the pump is off.

 

I had a local (tuner) guy take a look at the tune yesterday and it was pretty shitty. Too lean at idle, too fat up top, not nearly enough timing everywhere from idle to 6300 RPM.

Its fixed now and running much better.

Next mod is an LS6 intake (or better) and a bigger set of injectors (thinking a set of the white 36# GTP's). The 28# units now are at a 96% duty cycle at 6300 RPM in 3th gear.

I'll re-scan it today and post the readings.

 

You changed from a truck fuel rail (with manifold-referenced FPR between rails) to a car fuel rail (with un-referenced FPR in the tank), is this what you did...?

Are you sure that is the FPR (isn't that just the pulse dampner)...?

Post a pic.

 

I changed from a returnless style truck manifold/rail/injectors, to a returnless style LS1 intake/rails/injectors.

My gas tank is from a '02 Camaro Z28 with in-tank pump/regulator and I am also running a '99+ Corvette filter/regulator near (not on) the rail.

 

Ok, just a thought, returnless to returnless...

 

FUELSYS1 CL
FUELSYS2 CL
LOAD_PCT(%) 3.1
ETC(°F) 160
SHRTFT1(%) 0.8
LONGFT1(%) 19.5
SHRTFT2(%) 2.3
LONGFT2(%) 22.7
MAP(inHg) 15.9
RPM(/min) 658
VSS(mph) 0
SPARKADV(°) 13
IAT(°F) 88
MAF(lb/min) 1.433
TP(%) 15.7
O2S B1S12--B2S12--
O2B1S1(V) 0.265
SHRTFTB1S1(%) 2.3
O2B1S2(V) 0.445
O2B2S1(V) 0.050
SHRTFTB2S1(%) 5.5
O2B2S2(V) 0.440

 

yuck, you said you got that fixed... those are some high LTFTs.

 

What should they be?

 

close to zero... they indicate the underlying tables (VE and/or MAF) are off about 20% at the point of that snapshot.