Wow my LB7 is making me old. Mucho problemo
- Thread starter ArizonaCoal
- Start date
Talked to the mechanic today apparently when he told me he checked all the cylinders and none had compression he was just talking cause today he told me that he checked the timing gears and compression and the timing was on and had great compression in all cylinders. Now he is thinking that it has to do with the ECM again. Hes trying to get the original one fixed and sticking to his word that the new one I bought from ECM performance is and was junk when I bought it.
Anyone ever deal with ECM performance????
How do you fix an ECM that you can't communicate with?
Anyone ever deal with ECM performance????
How do you fix an ECM that you can't communicate with?
Get a new ECM from All Season Performance, Kennedy Diesel, Fleece, Scheid a reputable shop that you can tell details-on phone to help you just the first shops I had come to mind so you get help from EFI tuning guys, Mechant is another outfit to consider. Put in screw in injector cups for solid hold so injectors stay in. Just a new thing in a way Good Luck.
Just curious how a bad ECM will affect compression??? You need to get your truck out of there bub
Im not sure why this shop is makin you get the parts and not them? They should be flippin the bill to fix what they broke and iron it out at the end.
Id make those guys get the damn thing runnin, and runnin right then eat all the bs cost of the ecm and what not or cut your losses and go to the dealer.
Well talked to the mechanic today. He said he got the ECM to take the program and every thing is good but won't start. He sent it to his buddies shop to figure the rest out. Has no codes all pressures are prefect but will not fire is what he told me.
Also I guess he's trying to make it right. He told me he had it towed on a flat bed to the other shop at his cost.
Also I guess he's trying to make it right. He told me he had it towed on a flat bed to the other shop at his cost.
OK does the engine have compression in all cylinders or not???? You first said it didnt, then you said it did, then you said it didnt??? IF the engine doesnt have any compression, ill bet you the cam gear pin sheared. At least thats what it sounds like....
When the pin starts to shear, the cam timing will slip a couple degrees. The engine will still run fine with no apparent noises or issues HOWEVER you will notice it just doesnt have balls down low, and the turbo wont really spool as "snappy" as it used to.
Then after a while, it will get worse, until the pin completely shears in half, then the cam timing gets completely "off", and the engine wont run. It will probably have no or low compression in most of the cylinders, and when you crank it with the starter, it will sound like all the glow plugs are removed (ie, like theres no compression, the starter is just turning the engine over freely with no normal pup-pup-pup-pup compression-type noises that engines make when they are cranked).
When you take it apart, you'll find bent pushrods, maybe bent valves, and pistons with valve marks on them.
an anti-theft/security issue will cause the engine to fire for half a second, then stall. Not to mention, the security light will be flashing.
ben
When the pin starts to shear, the cam timing will slip a couple degrees. The engine will still run fine with no apparent noises or issues HOWEVER you will notice it just doesnt have balls down low, and the turbo wont really spool as "snappy" as it used to.
Then after a while, it will get worse, until the pin completely shears in half, then the cam timing gets completely "off", and the engine wont run. It will probably have no or low compression in most of the cylinders, and when you crank it with the starter, it will sound like all the glow plugs are removed (ie, like theres no compression, the starter is just turning the engine over freely with no normal pup-pup-pup-pup compression-type noises that engines make when they are cranked).
When you take it apart, you'll find bent pushrods, maybe bent valves, and pistons with valve marks on them.
an anti-theft/security issue will cause the engine to fire for half a second, then stall. Not to mention, the security light will be flashing.
ben
Man sound like your having hell. I took my truck to the dealer because my injectors where messy up they had a recall on them on the lb7. They told me they could not put them in because my heads where leaking water. I told them they where full of shit. My truck never ran hot or lost any water. So needless to say I got my truck out of their fast. I took my back to another dealer, when my gauges went out they fixed them no problem. then I told them to check my injectors they said they would have done them my truck had already passed the date. So I ended up putting my own injectors in.I got a good deal from Pensacola Diesel till running them today.
Thanks for the info. That was one of the things he checked or told me he checked. He was telling me it had no compression ten he told me it has compression. The latest was that all the numbers are good just won't start.
Other shop checked everything out. Everything comes back good. Rail pressure, pump pressure, no codes VATS been run through 4 times but injectors are not injecting any fuel. Any ideas. They talked with GM engineers numerous times and all they said was it should be working.
FICM?????? would send code? :help:
Any more ideas on what would be going on with this thing?
Just put brand new Bosh injectors.
New ECM with factory program.
New injector harnesses
FICM?????? would send code? :help:
Any more ideas on what would be going on with this thing?
Just put brand new Bosh injectors.
New ECM with factory program.
New injector harnesses
does it register RPM when cranking?
(I mean, does it show RPM on a scan tool, the cluster isnt gonna show anything because it shuts down when you turn the key to crank....but if you have a scan tool plugged in and monitoring data, it should show ~175-200rpm when cranking)
When you turn the key to crank, does the engine keep cranking as long as you hold the key to start, or does it only crank for a second or two and then cut off by itself, even though you are still holding the key to start???
(I mean, does it show RPM on a scan tool, the cluster isnt gonna show anything because it shuts down when you turn the key to crank....but if you have a scan tool plugged in and monitoring data, it should show ~175-200rpm when cranking)
When you turn the key to crank, does the engine keep cranking as long as you hold the key to start, or does it only crank for a second or two and then cut off by itself, even though you are still holding the key to start???
provided there are no mechanical problems, a duramax doesnt need much to start (as far as electronic-controlled engines go).
Basically all it needs is a working FICM, working ECM (and a learned anti-theft system), working fuel injectors, a crank sensor, a cam sensor, a rail pressure sensor, and ~1200psi of rail pressure. As long as you have all of those things, there is no reason it shouldnt start.
It doesnt need any other sensors plugged in, doesnt need the accelerator pedal plugged in, doesnt need a MAF sensor, baro sensor, MAP sensor, fuel temp sensor, oil pressure sensor, turbo sensors, EGR sensors, TCM, etc... Even with all of those things unplugged, it will still start and idle.
Basically all it needs is a working FICM, working ECM (and a learned anti-theft system), working fuel injectors, a crank sensor, a cam sensor, a rail pressure sensor, and ~1200psi of rail pressure. As long as you have all of those things, there is no reason it shouldnt start.
It doesnt need any other sensors plugged in, doesnt need the accelerator pedal plugged in, doesnt need a MAF sensor, baro sensor, MAP sensor, fuel temp sensor, oil pressure sensor, turbo sensors, EGR sensors, TCM, etc... Even with all of those things unplugged, it will still start and idle.
thanks for the info.... I will check with the guy that has it now and get back to this on sunday. I don't know about the RPMs but I'll ask.
it's been a while. Got the truck back to the shop at my work and been trying to chase the problem down. I sent the new ECM back and had the guy I bought it from reprogram it. Got it back and it seems to be working correctly. The mechanic that had it said before he did anything he changed the fuel filter and then it wouldn't start then he went ahead and changed the injectors and here we are... I will check to see if the scan tool is showing RPMS later today when all the normal people wake up.
This thing almost starts. It will run on starting fluid. Yes Yes I know we unhooked the glow plugs and all that before using it. only ran it for a half a second or so.
It acts like only one or two of the injectors are injecting. I get smoke out of the exhaust when trying to start.
This thing almost starts. It will run on starting fluid. Yes Yes I know we unhooked the glow plugs and all that before using it. only ran it for a half a second or so.
It acts like only one or two of the injectors are injecting. I get smoke out of the exhaust when trying to start.
this may seem like a stupid question but is it getting fuel at all? like past the filter itself? like its gotta air leak at the filter? dose the button stay prime? try pumping the button wile turning it over