7747 running issues

[kacy]

MY k10 with 350 tbi 700r4 342s and 33s shutters when in overdrive lock up at interstate speeds, lower speeds it isnt noticeable. It has happened since i bought it so far new dist. cap, rotor, coil, plugs, fuel pump, delco O2. I just changed the fp reg spring to one that had more pressure and turned in a screw for good measure (adapter and gauge in route) anyone care to decipher the log I recorded after reinstalling the new spring?

[mmigacz]

One of your early posts stated that you are planning on doing some modifications to this truck. Currently, is it stock? The reason I ask, is the tune seems to be messed up at highway speeds. The BLM’s are really high (150). It might even be maxed out, where the BLM cant go higher then 150. On a perfect tune they should be around 128 (+/- 5). Your trucks block learn (BLM) is adding fuel adding fuel to compensate for a lean condition. Another strange thing I noticed, was the O2 sensor is swinging around 300 mV. Usually, it swings around 450mv. Yours is swinging to the lean side of stoich. In my opinion your shutter is from a lean fuel mixture. Can you post your bin?

[kacy]

One of your early posts stated that you are planning on doing some modifications to this truck. Currently, is it stock? The reason I ask, is the tune seems to be messed up at highway speeds. The BLM’s are really high (150). It might even be maxed out, where the BLM cant go higher then 150. On a perfect tune they should be around 128 (+/- 5). Your trucks block learn (BLM) is adding fuel adding fuel to compensate for a lean condition. Another strange thing I noticed, was the O2 sensor is swinging around 300 mV. Usually, it swings around 450mv. Yours is swinging to the lean side of stoich. In my opinion your shutter is from a lean fuel mixture. Can you post your bin?Far as I know it's stock with no cat and true duals. I have seen the BLM up to 174 and is why I attempted to increase fuel pressure. I'll add the bin when I get to my PC.

[mmigacz]

Do you have the capability to change your tune yet? Chip burner or emulator? I have found that increasing fuel pressure does not richen the mixture up by large amounts. It does make it richer, but seems to have more an effect at high RPM's with high loads (when pressure might fall off).

[kacy]

Do you have the capability to change your tune yet? Chip burner or emulator?I do not.

[mmigacz]

I do not. How do you know the ASDU2 bin file you posted, is installed in your chip? Usually, you need a chip reader/burner to extract the bin file. Chips can be modified and re-burnt.

[kacy]

How do you know the ASDU2 bin file you posted, is installed in your chip? Usually, you need a chip reader/burner to extract the bin file. Chips can be modified and re-burnt.I dont, I used it because I read on here it is the best to use. The ecm appears to be a reman replacement as there is nothing on the case identifying the Mask.

[mmigacz]

Here is my advise.. Determine if the ecm has the chip adapter that allows it to use a 27SF512 chip. If it does, buy a chip burner (moates has them for $85)... After getting the burner/reader, download the actual bin file from your chip. You will need this when you do your vortec modifications. If you don't have the 27SF512 adapter (or don't know what I am referring to). post your answer and I can get you different directions.

[kacy]

is that the 28 to 24 pin conversion?

[mmigacz]

Yes it is. Just to be clear is converts 24 to 28 pin.

[kacy]

Yes it is. Just to be clear is converts 24 to 28 pin.close enough, chip says AMUR 0055 on it and its 24 pin

[kacy]

Oh I have also put a cap on the vacuum port for egr/air and disconnected the electrical connector.

[mmigacz]

If your not afraid of soldering a chip adapter into the circuit board, you can buy the 27SF512 adapter (G2 memory adapter) for $30 from moates. For another 8$ you can buy a 28 pin zif socket for easy chip removal. Moates has a tutorial on how to remove the 24 pin chip holder and how to solder the 24 to 28 pin adapter. (http://support.moates.net/g2-adapter-installation/)....Otherwise buying a new ECM with the chip adapter already installed in an option.

[mmigacz]

Oh I have also put a cap on the vacuum port for egr/air and disconnected the electrical connector. I'm not sure if that method of disabling the EGR is good or not. I don't use the EGR in my boat or Camaro. However, I disabled the EGR thru my tune.

[kacy]

I'm not sure if that method of disabling the EGR is good or not. I don't use the EGR in my boat or Camaro. However, I disabled the EGR thru my tune.its the only option I have to try and figure out what the problem is.

[kacy]

heres an update with egr and air reconnected. Using these

[mmigacz]

Did it run better??... The BLMs were way better... Also, did you have an error code when the EGR was unplugged? The o2 voltage was still swinging on the low side (350 mv), which is lean. On my Camaro I changed the swing to something closer to 600mv. It was happier when it was a little richer than stoich... BTW when you are datalogging, you don't have to have a bin file loaded into tunerpro. Currently, you don't know what your bin is, so its not worth posting something that is not installed in the ECM...

[kacy]

Did it run better??... The BLMs were way better... Also, did you have an error code when the EGR was unplugged? The o2 voltage was still swinging on the low side (350 mv), which is lean. On my Camaro I changed the swing to something closer to 600mv. It was happier when it was a little richer than stoich... BTW when you are datalogging, you don't have to have a bin file loaded into tunerpro. Currently, you don't know what your bin is, so its not worth posting something that is not installed in the ECM...so the AMUR code on the outside of the chip is irrelevant? The CEL did come on before this recording, it runs worse with those connected I have a spring that is rated for 12-20 psi at wot with a regulator made adjustable that will be installed when I get my gauge.

[mmigacz]

so the AMUR code on the outside of the chip is irrelevant? For datalogging, yes. Just because the chip has an AMUR label on it, it doesn't mean the original AMUR tune is still on it. It could of been flashed/retuned by somebody previous to you.

[jim_in_dorris]

I think something might be being ignored here, and that is the consequences of merely removing the EGR instead of disabling it in the tune. Because the tune doesn't know you don't have an EGR, when the EGR goes active in the tune, it expects to see the fueling lean out. if it doesn't, it will subtract fuel, making it lean. I think that you should get an ASDX tune with EGR disabled in the tune and go from there. ASDX is what I am currently running in my truck and it works quite well. Find someone to burn you a chip, it will be money well spent. I actually had a 305 tune in my truck and someone installed a 350 without changing the tune. I chased a lean condition for years before figuring out I actually had a 350. An unfortunate result of running lean is burned valves, so I am in the middle of doing a valve job now. Also, if the sticker is still on the chip, odds are extremely high that it is the original AMUR bin. To change the tune, you have to use a UV lamp to erase the chip which requires removing the sticker to expose the quartz window. 2732 chips are getting harder to find, but are still available.

[kacy]

I think something might be being ignored here, and that is the consequences of merely removing the EGR instead of disabling it in the tune. Because the tune doesn't know you don't have an EGR, when the EGR goes active in the tune, it expects to see the fueling lean out. if it doesn't, it will subtract fuel, making it lean. I think that you should get an ASDX tune with EGR disabled in the tune and go from there. ASDX is what I am currently running in my truck and it works quite well. Find someone to burn you a chip, it will be money well spent. I actually had a 305 tune in my truck and someone installed a 350 without changing the tune. I chased a lean condition for years before figuring out I actually had a 350. An unfortunate result of running lean is burned valves, so I am in the middle of doing a valve job now. Also, if the sticker is still on the chip, odds are extremely high that it is the original AMUR bin. To change the tune, you have to use a UV lamp to erase the chip which requires removing the sticker to expose the quartz window. 2732 chips are getting harder to find, but are still available.I would agree with you except the truck runs better with it disconnected and it takes a while for the CEL light to come on. What did the ASDX bin used in?

[jim_in_dorris]

ASDU is a 350 700r4 bin for trucks 3.73 rear gears. Eagle Mark and I did quite a bit of work on it documenting it before he passed. The EGR valve only comes on during certain conditions, closed loop cruise mainly. So until you reach those conditions, the EGR valve is not active. The CEL won't illuminate until the EGR valve is activated and it fails to go lean by the amount called for in the test. I currently have my EGR valve removed and a block off plate installed for test purposes. I do get a CEL but am okay with that. When I put the truck back together after the valve job, I will reinstall the EGR valve.EDIT!!! ASDU Is the correct bin I put ASDX BY MISTAKE. Looking at your symptoms, you either have a vacuum leak, a pre- o2 sensor exhaust leak, or incorrect injectors would be my guess. Try smoking or if you don't have a smoke gun, propane can help locate a vacuum leak. Also, verify your injectors by looking at the numbers stamped on them

[kacy]

It always smells rich at 750 rpm idle and 500 in gear, feels like it has more power than other tbi trucks. could I use a stock bin for a 350 1 ton because they didnt have emissions to rule them out?

[jim_in_dorris]

A stock bin for a 1 ton truck would most likely not be a very good idea, the 1 tons mostly had th400's for transmissions. it could be made to work, but why bother. Get ASDU with EGR disabled. I am not sure if AMUR is an open loop idle bin or not. Watch your data stream to see if it goes closed loop at idle.

[kacy]

A stock bin for a 1 ton truck would most likely not be a very good idea, the 1 tons mostly had th400's for transmissions. it could be made to work, but why bother. Get ASDU with EGR disabled. I am not sure if AMUR is an open loop idle bin or not. Watch your data stream to see if it goes closed loop at idle.Everytime I look at it at idle it is open loop and only thing the ecm controls is lock up and i put that on a toggle switch.

[jim_in_dorris]

ASDU is closed loop idle, much easier to tune for some people, others prefer open loop all the time. If tuning open loop. You need a wide band O2 sensor. With closed loop, a wide band is a big help, but not necessary. There is a lot of discussion on open loop tuning, but I like closed loop feed back systems. I cannot guarantee that ASDU would fix all your problems, but it might help, and certainly won't hurt.

[ony]

whatch the o2 voltage an see if it is getting hot enough at idle for closed loop. you may want to use a heated o2 sensor. my v6 4.3 would go open loop at 25-30 mph in 4th gear when it was cold in texas ,with a new sensor put a 3wire heated o2 in fixed the problem got better milage too.

[kacy]

the truck runs great when cold so if the o2 was open loop it should run great. I know it does run great with o2 disconnected i drove it like that for about 10 miles as a test.

[jim_in_dorris]

Ok, new info. If it runs ok in open loop, get a wide band O2 sensor and tune the open loop fueling to 13.5 AFR. Many people run open loop tunes. Not best possible fuel economy, but will run fine. If you want fuel economy, you will have to tune closed loop.

[kacy]

Ok, new info. If it runs ok in open loop, get a wide band O2 sensor and tune the open loop fueling to 13.5 AFR. Many people run open loop tunes. Not best possible fuel economy, but will run fine. If you want fuel economy, you will have to tune closed loop.i dont want to throw parts at it to attempt to fix it or cover the real issue. If that is the case ill pull the factory efi and go aftermarket efi.

[kacy]

Since i know nothing of this trucks history is there a chance that this engine could have come from a car with a roller cam and is why it is running lean?

[mmigacz]

Here is my advise.. Determine if the ecm has the chip adapter that allows it to use a 27SF512 chip. If it does, buy a chip burner (moates has them for $85)... After getting the burner/reader, download the actual bin file from your chip. You will need this when you do your vortec modifications. If you don't have the 27SF512 adapter (or don't know what I am referring to). post your answer and I can get you different directions. Did you give any thought to this? You can start trying some of the suggestions from others. Also, you will need to learn how to tune (change bin files) when the vortec mods are made.

[kacy]

I looked it doesnt have the 24 to 28 pin adapter, I haven't looked into getting the adapter and new chips/ burner. I was hoping to get this issue corrected or identified before i went and changed other stuff.

[kacy]

Did you give any thought to this? You can start trying some of the suggestions from others. Also, you will need to learn how to tune (change bin files) when the vortec mods are made.Is this the correct device you are refering to?

[mmigacz]

Is this the correct device you are refering to? It looks like it. Mine doesn't have a wire hanging off of it. Make sure it says G2 memory adapter (.06" leg spacing) when you buy it.

[lionelhutz]

Maybe I missed it but does your engine have any exhaust modifications? A non-heated O2 sensor tends to do poorly if it's not installed right in the exhaust manifold.

[kacy]

Maybe I missed it but does your engine have any exhaust modifications? A non-heated O2 sensor tends to do poorly if it's not installed right in the exhaust manifold.Factory manifolds, true duals no cat pipes violator mufflers

[mmigacz]

Is this the correct device you are refering to? That picture is not of the G2 adapter, its a 2timer. This is not what you need.

[kacy]

That picture is not of the G2 adapter, its a 2timer. This is not what you need.This from the link you used earlier in this post, this looks to tall to put the lid back on.

[kacy]

Looking at your symptoms, you either have a vacuum leak, a pre- o2 sensor exhaust leak, or incorrect injectors would be my guess. Try smoking or if you don't have a smoke gun, propane can help locate a vacuum leak. Also, verify your injectors by looking at the numbers stamped on themIf it were a vacuum leak wouldnt the IAC have lower than normal counts to compensate for the leak or a high idle if IAC cant compensate enough? Exhaust leak is a possibility i tried to get it to seal to the manifold hard to tell and without sliding under there with a bottle of soap and water if its a little one. Injectors is a possibility that I have considered just havent check yet as the truck is getting a shift kit installed for towing after I get these issues resolved.

[mmigacz]

I leave my lid off (since I'm swapping chips a lot). However, you can space the lid up with weather stripping to make clearance, if you are concerned with dust getting in. Also, that picture shows them using a spacer before the G2 adapter. You can omit the spacer and solder the G2 adapter directly to the circuit board. If you read the tutorial on moates they mention this.

[kacy]

sorry for all the questions, but are these chips reflashable or are they a one and done deal?

[mmigacz]

sorry for all the questions, but are these chips reflashable or are they a one and done deal? That's all right. I had my share of questions when I started... Yes, the 27SF512 chips are reflashable. For a starting point, I would buy (2). One for the ecm and one for changes.

[kacy]

Picked up an ASDU chip from pic a part yard, now shows 142 itn and 170 blm at idle using same adx and xdf, in the process i think I knocked a vacuum line for hvac off as I cant get air to blow from defrost or hot air.

[mmigacz]

sounds like you need to get that vacuum leak found. Somebody suggested getting a heated o2 sensor, did you try that too? Post the data log, I'm curious if the O2 swings are still on the lean side. Is egr connected?

[kacy]

sounds like you need to get that vacuum leak found. Somebody suggested getting a heated o2 sensor, did you try that too? Post the data log, I'm curious if the O2 swings are still on the lean side. Is egr connected?We are currently having an ice storm here so working on it is scarce, I have not tried a heater o2 as i just bought this single wire, egr is still disconnected. I have to get a new tv cable before I can drive it so logs would only be at idle.