no DR. my engine is like Danby said stock. I found this on the internet and the funny thing is I remember saying and seeing the exact same thing as this guy did.


Turbo Has Power Loss and Cherry Manifold: Knock Sensor. [Query:] My 740t intermittently looses power and the exhaust manifold turns bright red. I don't know if the two are related but when the car was in the loss power mode I opened the hood one night to check for arcing wires and I noticed the manifold glowing. [Response: Abe Crombie] Those are the symptoms of a knock sensor problem. The knock sensor may be bad but more likely the connector is the problem. When the ignition control unit detects no input from sensor the timing is retarded which is the safety from excessive spark knock but this does make engine power suffer and the delayed timing sends exhaust gas temp skyward.
One night right after it was acting up and I noticed that the temp was rising, I opened the hood and saw to the back center below was glowing bright red. In fact Danby just mentioned it a couple of post back...Weird?
I'm waiting for my tuner to call me back..He shoots me an email and say maybe it's your Catalytic converter. I don't think it is at all. for a few reasons.

 

I was holding off on my opinion of your tuner. Have they successfully tuned other lnf's? I don't want to offend anyone as I'm probably less experienced tuning an lnf then they are. But for them to call out a blocked converter as an issue first and foremost isn't looking good to me. I would find yourself a different tuner, at least for a second opinion. Not personally knowing them I won't knock anyone's skills. But as Dennis stated, the ecm does what it's told. I have some friends with an established speed shop and a 2000 hp chassis dyno. They tune the snot out of anything. They've been tuning for years, but those are LS motors and mustangs. I wouldn't let them tune my lnf. The 2 engines are worlds apart. When we were tuning my 94 firebird(N/A,LT4,534whp) I think there might have been 200-300 tables. The lnf has over 600 that deal with fuel management alone!

Now if we want to check your knock sensor connection that's easy peasy! Almost, lol. They are both located under the intake manifold. The hardest thing about getting to them is you'll probably need to disconnect the upper radiator hose and the top radiator mounts. You shouldn't lose much coolant if any. If you can get your hands in there you might not even need to move the radiator.

The radiator will pull forward almost 4" so you can look in and get your hands in there. If you need 8" there is 1x 10mm bolt holding your coolant overflow bottle in place. If you want to go that route, disconnect it from upper hose and yank it outta there. Now take a big sharpie and make a big line for the FULL level! Great 1 project done (lol, that was just for fun) The wife is out in the garage getting pics of the sensors as I write this. So pics soon.

But with the radiator pulled back you can probably see both knock sensors or at least their connectors. The connectors are pretty easy to get at. 1 is mounted to the dipstick about halfway down. The other is mounted to the support bracket that runs from the front of the intake to the block.

I'm not sure if you're aware but your new motor came with new knock sensors. Also, if they aren't properly connected I'd be hollering at that dealer of yours!

Pics 2 follow, it is nice to have a "reference" motor in the garage. Plus a wife, who knows where to find a knock sensor! LoL


Sensors are in orange, connectors are PURPLE

 

The beauty of the LNF operating system is that it always try to adjust the fueling to a lambda of 1, until you get into the upper ranges and depending on load and RPM it which point it will adjust according to the power enrichment table values.

If a knock sensor is detected as being bad and adjusting the timing I would have thought it would have thrown a code, P0324, P0326, P0327, P0328, P0331, P0332, P0333.

A blocked or failing cat will create all kinds of havoc so I wouldn't rule that out just yet.

Sounds like your wife is like mine... Makes life a lot easier that way.

black Tara, see if your tuner will send you your file, he should it's yours, you paid for it. I'll take a look at it to see if anything jumps out at me. Just to be clear, I will not share that information with anyone except you. We will have to have to converse off forum via email or PM.

 

I will see if I can get the tune emailed to me. What about the knock sensor? there are some similar things that happened to me,
But John says he doesn't think it's that.
Driving me crazy!!!!!!!!!
Danby did you get the long block or a complete new motor? I got the long blockand transferred over what ever parts I needed from the old motor

 

Not sure what you meant by this?

I got the complete LDK, I'm going to be porting and polishing the old head. After the wife gets used to all this power I intend on doing the cams, rods and pistons (in a few years, we've got plenty of power for now!)

Not sure if the long block would come with new sensors. Regardless, Dr. Loch obviously knows his stuff. I'd get that tune over to the doc asap. The ZFR turbo is a direct replacement for the K04, that is what you went with correct? Do you have an aftermarket downpipe? If you're still using the factory guy it could very well plugged up.

It sounds to me like I'm fairly broken in then. I'm still going to take it easy for a 1000 miles or so. I did follow proper break in procedures. Com cams break in oil, initial revs@ 2000, 4000, 6000. 200 miles later and now we're running pure mobile 1. Finally took off my slew of mechanical gauges out from under the hood! Oh, and finally got it to a car wash!

 

I got this one
GM ACDelco - LDK Long Block #ZZ-LDKLB


I just talked to my tuner, he wouldn't give me my tune.
But i'm having the car towed there first of the week. He said I'll find out what is wrong with it, Not to worry.
Be very interested at what hr finds hopefully it isn't something that cost me over $500.
Stay tuned. If anybody wants to post their guess, go for it. Be curious if someone hits it right on the head.

 

Yeah, it's HIS tune. We wouldn't hear that from him though. If you paid to have it done I see no reason not to give it to you, it's YOURS after all. You can't hurt anything without being able to flash it in the car. I assume he knows you don't have HP. I also assume he doesn't want knowledgeable folks like Dr. Loch to take a look. Honestly, I see no reason for this AT ALL. It's very easy to send the ecm code. The only reason not to would be it's the root of the problem.

Fishy bro, fishy.

I'm hoping for ya though, hoping that nothing melted internally. Definitely keep us in the loop.

My 2 cents

 

Not surprised. Some tuner think that what they are doing is top secret or rocket science and they don't want anyone to copy and/or benefit from there knowledge... If you had, or knew someone who has HPT they could suck it out although they would have to spend the credits to save it.

I'm very curious to find if it is mechanical or code related, please keep us updated.

 

I think you should consider getting hptuners and tune yourself. Then you can make changes based on a data log. Logs tell you a lot about what is going on and it will save you time and money. As for your shop that is tuning... I don't think its common for an LNF tuner to put a 25psi tune on a daily driver. I don't know if you requested that or not, but it is general LNF practice to stop at 23-24 on the stock block. Hopefully your pistons are fine. If your exhaust parts were glowing, your cats might be shot(not sure if you have stock dp)

 

X2!
My thoughts exactly. Tuners can be very touchy about their codes. Still, no reason not to share it with the cars owner.