twomanyjeeps

Hi all,

Been trying to put a LMG 5.3 out of a 2010 Suburban (~30,000 miles on it) into my 2003 crew cab s10. The harness and computer (E67 with stock colorado 5.3 tune) came from a reputable harness manufacturer that specializes in S10s.

My issue is the first start, the engine will just crank and won't really catch unless you pump the throttle. When it does finally run, it runs pretty rough and will stall out unless you give it throttle (~1200-1500 rpm) for about 15 seconds. Then it can "idle" on its own. The driver side bank is running rich enough to shoot gas out of the exhaust manifold. After less than a minute of running, the driver side manifold is too hot to touch ~200 degrees F, where as the passenger manifold is slightly less than half that temp. Put your ear to the driver side manifold and it sounds really throaty like its running on a huge cam. Passenger side sounds what I would expect to be normal.

MAF/air intake and O2 sensors are not hooked up, I assume the lack of O2 sensors wouldn't matter for open loop running.

My codes are a P0315 (crankshaft position system variation not learned); P0122 and P0223 which are throttle position sensor low circuit ones, and one for the MAF not being connected P0102. Also all the missing O2 sensor codes P0030; P0036; P0050; P0056.

What is also odd is the OBD scanner won't read anything for the short and long term fuel trims. It just stays at 0.

I've checked the pins on the harness to see if things like fuel injector connectors weren't pinned right. I've swapped the spark plugs left and right. I've checked cylinder compression. Everything with those checks are normal.

Other people with this issue swear by O2 sensors being the culprit, but I don't feel like that fits my problem since 1) Engine is in open loop and 2) no O2 sensors present to cause a problem.

Is it possible that the crank relearn for the P0315 code is so far out of whack that its causing this much of an issue? I feel like that would cause the whole engine to run like crap instead of just one bank.

Is there a mechanism for making the injectors on the driver side to keep shooting all the time? I know there not stuck open because the rail manages to stay pressurized for a couple days while just sitting.

Any other thoughts or advice on what else to look for is greatly appreciated.

Thanks,

rpturbo

iTrader: (47)

So I guess the harness is CPW? At any rate, your not going to like what I say, but start simple. Get the O2's in it! Regardless of saying its in open loop. Has the ecm been programed at all or just the vats disabled?

How do you think the scanner will read stft and ltfts without O2's?

As far as the injectors go, they open and close by ground. You may have a bad ground issue if you think the injectors are stuck open. I would suggest a noid light if you can access one, and IF Jared did the harness, give him a call, he has great customer service, but be warned, he will tell you to install O2's as well.

twomanyjeeps

Don't worry, O2 sensors are on the way. I just don't want to put the cat on that side cause the engine will ruin it in a heartbeat. But maybe just having some kind of input signal might improve my situation. Just wondering if there might be something else that I'm overlooking. I have no experience with engines this advanced.

I've checked and rechecked the grounds but I can always try changing that up too.

The computer has had a base colorado tune and OS applied to it with VATS disabled and that's about it, nothing else special.

Thanks and I'll update once I get the O2 sensors put in.

rpturbo

iTrader: (47)

Do you have that thread up on the s10 site asking about the wiring of O2 sensors?

I don't know anything on the Colorado base tune. I can't say I know anyone who runs that as a base. Do you have any plans on running a/c? The reason I ask, is there are 2 types of compressors, and the OS base, makes a difference as to what they will run. If you are, what compressor are you going to run? If not, it makes really no difference.

Since at this point, the ECM hasn't been programmed, if you have the MAF, connect it up as well with the O2's. Start there, getting it running correctly, then you can swap it over to a SD tune when you have it tuned or tune it, but just try to make your own life easy by giving it what it's looking for, and knowing you have a solid running swap, before you change things.

twomanyjeeps

I've got a PM out to the one guy I know over there who runs the colorado computer and OS. I haven't heard back yet. I believe the colorado computer and OS is required if you wanted to keep VVT and AFM and still have the computer run things like the gauges (according to the harness manufacturer).

As far as AC compressor, I'll be running a sanden type. As far as running AC and tuning the rest of the computer, I'll burn that bridge when I get to it. Like you're saying, the plan is to see the thing run without dumping fuel and fireballs out the driver side manifold before I reassemble the rest of the truck. Then I'll start changing things to get everything dialed in and worrying about things like AC.

twomanyjeeps

I thought I'd follow up on this thread because I hate threads that never have a conclusion.

I haven't really touched the truck in the last couple months due to the weather being hot as hell and busy with other aspects of life. I did talk to Jared who confirmed my thoughts about being better off without the O2's plugged in. I did however get a MAF plugged in and a mock air intake setup.

What it finally ended up being was ALL the injectors on the pass side weren't firing. I thought that the passenger side was running when I first made this thread because it was slightly warm after about 15 seconds of trying to run but wasn't "burn your hand hot" like the driver side was. Also on both sides, the runners of each respective manifold are all the same temp. I didn't think that ALL the injectors, coils, whatever on one whole side would be the culprit. I finally did a sanity check with my older jeep and ran it for 15 seconds to get a feel for how hot an engine should be after a short time and it confirmed that the driver side was the normal side. I guess whatever heat I was feeling the on the passenger side was just conducting over from the driver side.

I tried jumping all the injectors on the pass side and could only hear a faint click. Then repeated on the driver side to find out that a healthy injector is MUCH louder. I tried the boiling trick on the bad ones and boiled them for about 30 minutes and they still wouldn't fire like the driver side one. Finally just bought four new ones and surely enough, the engine runs fine on both sides now.

It runs like I would expect an old motor with open headers to run and all those original codes are still there, but now the next step is to quit being so lazy, get the radiator in so I can do some extended runs and get everything dialed in. Then finally get this thing on the road.