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Discussion Starter · #1 ·
Alright fellas, as many already know, I just dropped my rebuilt LT1 in my Impala and with the help of the forum, trying to sort out some issues.

Just did my second fill-up on the new motor and I'm seeing about 8mpg (140 miles to 18 Gal). I noticed this on the first fill-up but figured it was the lack of a tune and a slipping trans for the first half a tank.

I now have a tune (PCMForLess), a good trans, and still 8mpg. I also noticed on my initial 200 mile oil change that the oil was pretty thin and smelled like fuel. I'm thinking maybe a stuck injector or too much injector (lucas 30lbs). Should I stay with the stock injectors for my setup? Are my rings not yet fully seated? (300 miles)

Mods:

-CC 503 Cam
-Lucas 30lb injectors
-Ported Aluminum heads (F-Body)
-58mm TB
-Yank SS3600 Stall
-Tri-Y headers
-No Cats
-stock 3.08 gears (I know, I know.....)

Car is currently at the paint shop and I will be out of town till mid Nov so no hands on for now. Just hoping you guys can kick down some ideas and experience on what I should check first.
Has new fuel filter, spark plugs, cap & rotor.
 

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On the rings, I am a big believer on having the engine torque break a few times down a hill to seat them.
Then going up the hill gradually get into the throttle to about 3/4's.
You will get worse gas mileage on the first few tanks, but that seems really low unless your foot was in it a lot.
Could be a stuck injector, but if the rings are not seated fully could be the problem also.
I like 30# injectors, but the Ford SVO ones. I would make sure Bryan knew they were Lucas and not SVO, reason is the offset for them in the programming.
Need to get a datalog of the car and see if it really is dumping fuel. if it is then you could just have an intake or exhaust leak causing it.
 

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I"m also a believer in lots of load to help seat rings...both acceleration and deceleration.

Personally, my new engine will be "finished" shortly (maybe tomorrow) at which point I'm bringing it home to fully dress it (valvecovers, injectors, balancer...all that jazz) and then bringing it BACK to the builder, to fire it for the first time, on his engine dyno, and make a few WOT pulls which should help make sure everything is ok, and give me piece of mind that it's a solid happy engine.

After that I'll take it home and put it in the car.
 

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Sounds waaay too bad to be rings. Are you getting a CEL? Were you sure to use sensor-safe Permatex? It's not unusual if you don't to ruin the O2 sensors.
 

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Discussion Starter · #5 ·
I did get a CEL twice in the last 300 miles-Bank 2, sensor 1=No Activity. It took about 70 miles to come on the first time and over a hundred to come back but I will change them both for safe measure.

Sensor Safe Permatex? Honestly...I'm not sure.

Wish I could datalog whats going on, I'm not too computer saavy and wouldn't know what to look for, nor do I have the equipment. Anyone near Sacramento, CA want to help me on this one?

Don't think I actually specified Lucas VS SVO with BH but will check my order sheet and contact him if need be.

How many miles does an engine generally require for the rings to fully seat?

My trip to the paint shop was the cars first uphill experience and with that recommendation I will run that hill a couple more times.

Thanks for the advice guys!
 

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Put a fuel pressure gauge on the fuel rail. Turn the key on and check the pressure. Start the engine and check the running fuel pressure. After that, turn off the engine and check for bleed down. If that's all good, even if it's not, pull the vacuum line off the fuel pressure regulator and check for fuel. I had a failed FPR in our 95 9C1 and it idled rough, smelled of fuel, thinned the oil and got bad mileage. Liquid fuel poured out the FPR when I removed the vacuum hose. That shouldn't happen at all.
 

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I will tell you how I treated my heads and cam engine after building it.
Torque break a few times, gradually on the throttle.
Then about 10 minutes after first start up, go after it.
Drove for 150 miles. Changed the oil. Drove 1000, changed the oil.
Never babied it, just drove the car normal.
I would check, change that O2 sensor, that could be it, no activity, dumps fuel.
Since swapping engines might be the harness also.
 

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Double check the O2 harness connections, since you had all that stuff out, the left rear and the right front can be swapped if you didn't label them if removed, I ran into this issue on a car I worked on, late nights and not double checking that the connections were right caused an O2 CEL, but it was low voltage CEL. Mind you I put a T56 in this car and you would think by the harness break outs that this couldn't be done, but it can. Just a double check to make sure can save you an ass load of troubleshooting time. From my experience even if the sensor is bad to a point, minus being shorted or open internally, you will still get some activity and it would pop the low voltage or high voltage if it is clogged up with permatex, check also to make sure that the O2 sensor lead didn't get melted by headers or something like that.
Fuel pressure or sticking injector sounds feasible as well.
 

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careful you don't wash down a cylinder

fix the problem asap, don't keep driving it until you are sure what the issue is

everyone's trying to help but don't keep pumping gas into your oiling system
 

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^^^^^^!!!!!!!

Like BK said.....real easy to do. My wife's car has a lumpy cam with a 106 LSA. We got it out of the shop, I drove it for a few minutes and then turned it over to her to drive 4 hours to HOSSfest. She wasn't used to the car and didn't notice that the long tube headers burned a wire and drove it for those 4 hours pumping gas into a dead cylinder. Long story short....I've got a $12,000.00 engine that needs an overhaul. Get that thing running right before you do the same! Bill.
 

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Discussion Starter · #11 ·
All good info guys, I do appreciate it.

After following the necessary troubleshooting tasks, will a compression and/or leak down test show me if I washed a cylinder out?

Jerry
 

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Discussion Starter · #12 ·
Just got my car back.......

I haven't forgot about the info all of you have shared to help me with my problem but after two months, I just got my car back from the paint shop!

I regret to say that I am very dissapointed with both thier service and work. But that is another topic.

I did some troubleshooting on my car as follows:

-Checked my order sheet with BH, Lucas-30lb injectors was indicated.

-Checked Fuel Pressure
--Key On = 40psi
--Running idle = 47psi
--Part throttle = 44psi
--Key Off = Dropped to 36psi then raise to 45psi
--After 1 hour = 36psi
--After 2 hours = 27psi

-No Fuel on FPR Vacuum hose

-I installed an Evap Canister as it was missing and the hoses were bypassed.

-Checked the ECT on WP
-- around 2k ohms cold--70 deg
-- around 400 ohms warm-- 160 deg
Not sure what the standard is but thought I would check it.

-Re-adjusted RR's running (Wet Lash)

-Doublechecked O2 sensor harness on Pass side (Bank 2). Swapped with open rear plug just to check-CEL came on immediately, swapped back.

-Replaced O2 sensor (Bank 2 , Sensor 1)

By looking at my FP reading, could I have a sticking/leaking injector? Is this normal? I have a set of Red top 30lb injectors to swap in but need to check with BH on tune compatibility.

BTW: I changed my oil just after the previous work and it was full of fuel and very thin. I replaced it with Valvoline VR1 High ZDDP non synthetic.
 
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