K5 TBI conversion idle issues (WINALDL)
01-16-2011, 11:41 AM
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K5 TBI conversion idle issues (WINALDL)
Hi guys!
I’m new the forum and need a little bit of help. I did a TBI conversion intake swap with my K5. I used a painless harness and the idle “haunts” between 900-525 and sometime stalls.
I’ve already reset the IAC and bumped up the idle screw a half of turn. I have check for vacuum leaks and I found none.
Everything is new except the EGR and the distributor which I checked with a hand pump and held 12 lbs for 1 minute.
I did datalog, I was wondering if anyone could help me read the file?
Thank you,
Crittle
I’m new the forum and need a little bit of help. I did a TBI conversion intake swap with my K5. I used a painless harness and the idle “haunts” between 900-525 and sometime stalls.
I’ve already reset the IAC and bumped up the idle screw a half of turn. I have check for vacuum leaks and I found none.
Everything is new except the EGR and the distributor which I checked with a hand pump and held 12 lbs for 1 minute.
I did datalog, I was wondering if anyone could help me read the file?
Thank you,
Crittle
01-18-2011, 03:09 AM
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Re: K5 TBI conversion idle issues (WINALDL)
Not really positive what I was looking at, were you blipping the throttle slightly while logging? Your TPS and MAP were moving around a bit. Your rich/lean counter started incrementing once you warmed up, so your O2 is working. Your IAT count went down when it warmed up, but still seems a little high, mine sits at ~35-40 at warm idle.
01-18-2011, 12:29 PM
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Re: K5 TBI conversion idle issues (WINALDL)
Jim,
Thank you for taking a look. I took the Blazer for a spin around the block and got on it a few times that is why the numbers are probably moving around.
I converted to a heated O2 sensor, so closed loop should have be done quickly.
Is it better to run WINALDL at idle or under driving conditions?
Thank you for taking a look. I took the Blazer for a spin around the block and got on it a few times that is why the numbers are probably moving around.
I converted to a heated O2 sensor, so closed loop should have be done quickly.
Is it better to run WINALDL at idle or under driving conditions?
01-18-2011, 12:42 PM
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Re: K5 TBI conversion idle issues (WINALDL)
You have a problem if you were driving around. Your VSS is not hooked up. your vehicle speed during your entire drive was 0. I assumed you were parked because of that. If you are trying to find why it hunts at idle, you need to take a log of that happening. You want to take logs of the event you are trying to diagnose, be it an idle condition or a driving condition.
01-18-2011, 09:48 PM
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Re: K5 TBI conversion idle issues (WINALDL)
After I got home from work I took another sample. The problem only seems to occur in closed loop only. Mr. Jim would you mind taking another look?
Thank you advance!
Thank you advance!
01-18-2011, 11:59 PM
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Re: K5 TBI conversion idle issues (WINALDL)
WOW it actually runs? What temp thermostat do you have in it? Your O2 sensor is not working in this sample, and you are not getting rich/lean transition. You are also running extremely rich (like how can it run that rich)
01-19-2011, 12:06 AM
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Re: K5 TBI conversion idle issues (WINALDL)
It looks like WinALDL isnt set up properly. None of the data there makes any sense. What are your current WinALDL settings? What ECM did you use for the conversion?
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01-19-2011, 10:16 PM
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Re: K5 TBI conversion idle issues (WINALDL)
Sorry for not responding earlier but I worked super late tonight.
Jim,
The Blazer does run, but not the greatest. The thermostat is 180 deg. I thought it smelled rich. I don't know what is causing these issues. I have no error codes.
Dimented,
I took a snapshot of my configuration. I'm running an 7747 ECM for the conversion.
Jim,
The Blazer does run, but not the greatest. The thermostat is 180 deg. I thought it smelled rich. I don't know what is causing these issues. I have no error codes.
Dimented,
I took a snapshot of my configuration. I'm running an 7747 ECM for the conversion.
01-20-2011, 12:15 AM
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Re: K5 TBI conversion idle issues (WINALDL)
Ok, first you need to put a 195 thermostat in. That is what your default program is looking for, and unless you change values in the tune, it will think it is not warmed up and continue to run rich. This may not fix your problems, but it is a start. Second, I am not sure that your data is correct because your configuration shows an error for the port setup. If you took that snapshot without being attached to the truck and the truck turned on then it is ok. I use WINALDL and my truck is also a 7747.
I think that I remember somewhere that the ground for the 3 wire O2 sensor must be the ECM ground to work properly, one wire is key-on 12 volts, and one is the connection to the ECM. Have you had your dash out? like I said, it looks like your VSS is not connected. Looking at one of my logs, my IAC at idle is 13 - 20, my map is ~27-42 my TPS is .2-.7
I think that I remember somewhere that the ground for the 3 wire O2 sensor must be the ECM ground to work properly, one wire is key-on 12 volts, and one is the connection to the ECM. Have you had your dash out? like I said, it looks like your VSS is not connected. Looking at one of my logs, my IAC at idle is 13 - 20, my map is ~27-42 my TPS is .2-.7
01-20-2011, 08:52 AM
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Re: K5 TBI conversion idle issues (WINALDL)
Ok, first you need to put a 195 thermostat in. That is what your default program is looking for, and unless you change values in the tune, it will think it is not warmed up and continue to run rich. This may not fix your problems, but it is a start. Second, I am not sure that your data is correct because your configuration shows an error for the port setup. If you took that snapshot without being attached to the truck and the truck turned on then it is ok. I use WINALDL and my truck is also a 7747.
I think that I remember somewhere that the ground for the 3 wire O2 sensor must be the ECM ground to work properly, one wire is key-on 12 volts, and one is the connection to the ECM. Have you had your dash out? like I said, it looks like your VSS is not connected. Looking at one of my logs, my IAC at idle is 13 - 20, my map is ~27-42 my TPS is .2-.7
I think that I remember somewhere that the ground for the 3 wire O2 sensor must be the ECM ground to work properly, one wire is key-on 12 volts, and one is the connection to the ECM. Have you had your dash out? like I said, it looks like your VSS is not connected. Looking at one of my logs, my IAC at idle is 13 - 20, my map is ~27-42 my TPS is .2-.7
01-20-2011, 07:48 PM
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Re: K5 TBI conversion idle issues (WINALDL)
I will grab 195 deg thermostat and give it a whirl. WINADL was NOT hooked up when I took the picture I will hook it up and try again. I have the dash apart currently and the VSS is not hooked up yet (Sorry I should have posted it earlier).
I think I have a pretty good ground on the O2 sensor I have attached a picture.
Question! Do I need another chip burned? I don't have the numbers of the cam profile, but it's nothing special.
I think I have a pretty good ground on the O2 sensor I have attached a picture.
Question! Do I need another chip burned? I don't have the numbers of the cam profile, but it's nothing special.
01-20-2011, 08:21 PM
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Re: K5 TBI conversion idle issues (WINALDL)
Right now I wouldn't worry about burning a chip for it until you can get the other stuff sorted out. If you are running it without the VSS hooked up it should throw a code, I know mine did. I didn't see any codes set in your logs. You may still have a vacuum leak. How did you check for leaks? I really don't understand why your O2 sensor doesn't seem to be working properly either. Can you back probe it to see if the voltage is actually changing? The fact that WINALDL is talking tells me that your ECM is most likely fine. I do wonder about your sensor grounds however, that may be what we are fighting on the MAP, IAC and TPS. Did you put the ground strap between the rear of the passenger head and the firewall back? I am really puzzled about the values I am seeing in your logs. Warm your truck up to operating temps and take about a 3 min log at idle and see what your IAC counts are, what the O2 sensor is doing, and if the rich/lean counter is incrementing.
01-20-2011, 09:17 PM
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Re: K5 TBI conversion idle issues (WINALDL)
That ground wire in your picture is questionable as well. It may be OK if all the parts under it are clean, unpainted metal AND you have a ground strap from the motor to firewall... even if it were not good I don't think it's your only problem...
01-20-2011, 10:00 PM
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Re: K5 TBI conversion idle issues (WINALDL)
Thanks for the replies as always.
My trucks does not throw any codes. It did throw a code when I set the timing a few weeks ago, so I know that it is reading the "errors"
My vacuum leaks were checked using three methods.
1.) The old carb cleaner trick
2.) NON-LIT propane tank method
3.) Covered the TBI and used a smoke machine with a large water bottle and pushed approx. 3 lbs of air through the container into the intake port (it was a little goofy but it work).
It might be a little hard to probe, because I have a weather pack connector.
I don't recall seeing a ground strap, but I need to double check.
Lately the truck wants to die on me, so I hope that I can get a 3 min idle test.
My trucks does not throw any codes. It did throw a code when I set the timing a few weeks ago, so I know that it is reading the "errors"
My vacuum leaks were checked using three methods.
1.) The old carb cleaner trick
2.) NON-LIT propane tank method
3.) Covered the TBI and used a smoke machine with a large water bottle and pushed approx. 3 lbs of air through the container into the intake port (it was a little goofy but it work).
It might be a little hard to probe, because I have a weather pack connector.
I don't recall seeing a ground strap, but I need to double check.
Lately the truck wants to die on me, so I hope that I can get a 3 min idle test.
01-21-2011, 01:21 AM
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Re: K5 TBI conversion idle issues (WINALDL)
Its been at least 8 or 10 years since Ive used winaldl so I dont remember much about it, but from your (crittle's) datalog, it looks like the baudrate may be wrong, or possibly the definition file isnt correct. What happens when you try the default baudrate of 2400?
01-21-2011, 03:37 AM
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Re: K5 TBI conversion idle issues (WINALDL)
Thanks for showing up dimented, I use the same baud rate as crittle without a problem, and winaldl has the definition file built into the ecm selection, I am not sure you can change it. If he was using tunerpro I could understand that concern. I agree he should try changing the baud rate, but I think that he has something else going on. I think he needs to answer another question, was the truck tbi before he did the intake change, and more importantly, is the ecm the same as from before?
01-22-2011, 09:49 PM
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Re: K5 TBI conversion idle issues (WINALDL)
I have not looked at the thermostat or o2 yet.
The tbi conversion is on an 80' K5 blazer with a 700r4 tranny with a 205 transfercase.
The intake/throttle body/dist/ecm and brackets were from an 88' chevy truck.
No data comes thru at 2400 baud rate
The tbi conversion is on an 80' K5 blazer with a 700r4 tranny with a 205 transfercase.
The intake/throttle body/dist/ecm and brackets were from an 88' chevy truck.
No data comes thru at 2400 baud rate
01-22-2011, 10:02 PM
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Re: K5 TBI conversion idle issues (WINALDL)
Thanks, the info you supplied may help. I think you have a ground problem. Grounds are critical in ECM systems. It uses a reference voltage to ground, and if the ground is floating, it will drive you nuts. I would start with a good voltmeter and check all the sensors and the ecm ground. Also make sure that the engine to firewall ground is there. This is critical to figuring out what is going on with your truck, until you are completely certain about grounds, we can be certain about nothing else. Keep us informed
02-26-2011, 09:57 AM
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Re: K5 TBI conversion idle issues (WINALDL)
Ok guys! Finally had some some time to work on the Blazer...
What I did.
1.) Added ground straps to the frame and chassis
2.) Verify I had a 195 degree t-stat
3.) Checked and replaced the heated O2 sensor
I give up! It still does not run well we warm.
Any advice?
Thanks, Crittle
What I did.
1.) Added ground straps to the frame and chassis
2.) Verify I had a 195 degree t-stat
3.) Checked and replaced the heated O2 sensor
I give up! It still does not run well we warm.
Any advice?
Thanks, Crittle
02-26-2011, 01:24 PM
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Re: K5 TBI conversion idle issues (WINALDL)
Make sure your map sensor is hooked to manifold vacuum, measure the vacuum at the different ports, you want the highest reading one(at idle) going to the map.
Double check your ecm grounds, GMs run funny w/ bad grounds.
Check your ignition timing(might advance it alittle too) & make sure it advances when you rev it. Is there a wire you have to unhook to set the timing? Original tbis you had to unhook a wire to set base timing.
Measure your fuel pressure, might have a blocked return line causing high fuel psi.
Double check your ecm grounds, GMs run funny w/ bad grounds.
Check your ignition timing(might advance it alittle too) & make sure it advances when you rev it. Is there a wire you have to unhook to set the timing? Original tbis you had to unhook a wire to set base timing.
Measure your fuel pressure, might have a blocked return line causing high fuel psi.
02-26-2011, 06:10 PM
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Re: K5 TBI conversion idle issues (WINALDL)
Have you done a log recently? Does your CTS temp register 195? are you going into closed loop? It's obviously a closed loop problem. Is your VSS hooked up now? Does your IAC count change with the idle surging?
02-27-2011, 03:44 PM
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Re: K5 TBI conversion idle issues (WINALDL)
Well I looked at the log and I see a few things different.
First you say you have a 7747 ecm but I can not find a scan ID of 4551 for a 7747 ecm.
I can find it for an 8747 ecm which was for the heavy truck application.
So first you need to post what the 4 letter code is that is printed on the large chip in the ecm.
Then "if" the 8747 uses the same aldl definition file so your data is even correct......I see you have not performed an initial setup procedure.
Here's my basic guidelines.
After that you need to disconnect the pk/n wire. It is not used in manual applications and will confues the ecm if you try to drive around with it always in pk.
It also sounded like in your first post you you said you checked the vacuum advance on the distr with a hand pump?????????????/
There is no distr advance in TBI. so the mech must be locked and the vacuum hose disconnected.
The temp does not need to be 195..... 180 will work fine.
I know it's hard when starting out to know who is telling you the correct fixes but your system needs to be right before you even worry about tuning.
Some people start in the middle with trouble shooting.
I lkie to start with a known good system first.
Your first log is attached. The second is junk.
You need to uncheck the raw box and check the rest.
The mods need to add XLS to the upload file types.
First you say you have a 7747 ecm but I can not find a scan ID of 4551 for a 7747 ecm.
I can find it for an 8747 ecm which was for the heavy truck application.
So first you need to post what the 4 letter code is that is printed on the large chip in the ecm.
Then "if" the 8747 uses the same aldl definition file so your data is even correct......I see you have not performed an initial setup procedure.
Here's my basic guidelines.
I know the first thing guys want to do when hooking up their fuel injection set up is to start it up and hear it run....
Well there are a couple things that need to be done after the installation.
1. Timing- There are 2 ways to do this.
a. disconnect the bypass wire and set timing to 0° at idle when warm. procedure- warm up motor then turn off. unplug bypass. Start motor. Set timing to 0°. Turn off motor. Reconnect bypass. Unplug ECM to clear fault code.
b. leave bypass connected and set timing to the value listed for your idle rpm and MAP setting at idle, based on your specific BCC-broadcast code. Procedure-start motor and warm up. Set timing to the value listed in the spark table.
2. IAC reset/min idle speed- This sets the throttle plate on the throttle body to a specific rpm. I recommend about 500 rpm for most engines. Procedures- Go to sheet 7 of the pinout diagrams. At the top is the ALDL connector. You need to put a jumper between pins A and B of the connector. These are pins A9(wht/blk) and A12 (blk/wht) on the ECM. This puts the ECM into aldl mode. Turn the key on (not start) and the IAC should drive completely closed. You will normally hear a buzzing from the IAC. If you have the winaldl up and running on your laptop, you should see the IAC went from 145 to 0. Now unplug the IAC connector. turn the key off. Remove jumper. Start motor. If the idle is too low you may have to keep it running. On the front drivers side of the throttle body is the adjustment screw. It may be behind a silver plug. If so just use a nail or punch to poke it and remove it. Then use a #20 torx bit to adjust the idle speed to at least 100 rpm less then your warm idle speed. if 600 then set to 500 rpm. You are looking for the lowest consistant idle your motor will do. When set, turn off motor and reconnect the IAC. I try to keep the IAC count to at least 40 with the motor warm and idling.
This is a good time to verify the operation of the IAC. When the jumper is in and the key is on the IAC is driven closed. So while it is idling to set min rpm put a finger over the IAC port just above the IAC. There should be no air being sucked in and you should be able to see the pintle on the IAC.
When the IAC is connected and operating there should be a small amount of air being sucked in the port at idle and should increase as you apply some throttle.
3. TPS-throttle position sensor. With the idle set, you need to now set the TPS. This need to be set to about .54V. I normally shoot for about .6V.
The TPS is on the passengers side and will have 2 screws holding it on. The factory TPS will not have much room in the holes for adjustments so I use a drill bit or file to elongate the holes as needed. To adjust, just loosen the screws and trist the TPS. You can monitor the voltage on Pin B of the connector with the key on or at pin C13 of the ECM. You can also see it on the sensors tab of winaldl!! Anything away from .54V will also show as a percent of throttle. Such as .2 percent or 1.7 percent...depending on how far from .54v you are. I try to keep the idle setting to within 1 percent.
This is also a good time to check your TPS. Once it is set, just watch the voltage as you open the throttle. you should see a steady rise in voltage up to about 4.5-5V at WOT-wide open throttle. If it jumps up and down or skips some then you may want to replace it.
4. Fuel pressure- The system calculates the fuel needed based on the initial settings for injector size at a specific pressure. If the pressure changes then the fuel calculations will be off. I recommend checking the feed and return line pressures at the very beginning. This can save a lot of time later. The pressure is less then 15PSI so a simple cheap gauge is all that is needed. I picked up a HF fuel inj tester for $7 on sale. Comes with a T and a short rubber hose to install it.
The feed side pressure should be about 13psi and should not change with rpm or load. The return should be near 0psi.
Well there are a couple things that need to be done after the installation.
1. Timing- There are 2 ways to do this.
a. disconnect the bypass wire and set timing to 0° at idle when warm. procedure- warm up motor then turn off. unplug bypass. Start motor. Set timing to 0°. Turn off motor. Reconnect bypass. Unplug ECM to clear fault code.
b. leave bypass connected and set timing to the value listed for your idle rpm and MAP setting at idle, based on your specific BCC-broadcast code. Procedure-start motor and warm up. Set timing to the value listed in the spark table.
2. IAC reset/min idle speed- This sets the throttle plate on the throttle body to a specific rpm. I recommend about 500 rpm for most engines. Procedures- Go to sheet 7 of the pinout diagrams. At the top is the ALDL connector. You need to put a jumper between pins A and B of the connector. These are pins A9(wht/blk) and A12 (blk/wht) on the ECM. This puts the ECM into aldl mode. Turn the key on (not start) and the IAC should drive completely closed. You will normally hear a buzzing from the IAC. If you have the winaldl up and running on your laptop, you should see the IAC went from 145 to 0. Now unplug the IAC connector. turn the key off. Remove jumper. Start motor. If the idle is too low you may have to keep it running. On the front drivers side of the throttle body is the adjustment screw. It may be behind a silver plug. If so just use a nail or punch to poke it and remove it. Then use a #20 torx bit to adjust the idle speed to at least 100 rpm less then your warm idle speed. if 600 then set to 500 rpm. You are looking for the lowest consistant idle your motor will do. When set, turn off motor and reconnect the IAC. I try to keep the IAC count to at least 40 with the motor warm and idling.
This is a good time to verify the operation of the IAC. When the jumper is in and the key is on the IAC is driven closed. So while it is idling to set min rpm put a finger over the IAC port just above the IAC. There should be no air being sucked in and you should be able to see the pintle on the IAC.
When the IAC is connected and operating there should be a small amount of air being sucked in the port at idle and should increase as you apply some throttle.
3. TPS-throttle position sensor. With the idle set, you need to now set the TPS. This need to be set to about .54V. I normally shoot for about .6V.
The TPS is on the passengers side and will have 2 screws holding it on. The factory TPS will not have much room in the holes for adjustments so I use a drill bit or file to elongate the holes as needed. To adjust, just loosen the screws and trist the TPS. You can monitor the voltage on Pin B of the connector with the key on or at pin C13 of the ECM. You can also see it on the sensors tab of winaldl!! Anything away from .54V will also show as a percent of throttle. Such as .2 percent or 1.7 percent...depending on how far from .54v you are. I try to keep the idle setting to within 1 percent.
This is also a good time to check your TPS. Once it is set, just watch the voltage as you open the throttle. you should see a steady rise in voltage up to about 4.5-5V at WOT-wide open throttle. If it jumps up and down or skips some then you may want to replace it.
4. Fuel pressure- The system calculates the fuel needed based on the initial settings for injector size at a specific pressure. If the pressure changes then the fuel calculations will be off. I recommend checking the feed and return line pressures at the very beginning. This can save a lot of time later. The pressure is less then 15PSI so a simple cheap gauge is all that is needed. I picked up a HF fuel inj tester for $7 on sale. Comes with a T and a short rubber hose to install it.
The feed side pressure should be about 13psi and should not change with rpm or load. The return should be near 0psi.
It also sounded like in your first post you you said you checked the vacuum advance on the distr with a hand pump?????????????/
There is no distr advance in TBI. so the mech must be locked and the vacuum hose disconnected.
The temp does not need to be 195..... 180 will work fine.
I know it's hard when starting out to know who is telling you the correct fixes but your system needs to be right before you even worry about tuning.
Some people start in the middle with trouble shooting.
I lkie to start with a known good system first.
Your first log is attached. The second is junk.
You need to uncheck the raw box and check the rest.
The mods need to add XLS to the upload file types.
03-18-2011, 10:58 PM
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Re: K5 TBI conversion idle issues (WINALDL)
Problem solved!!!!!!!!!
Thank you Jim and Bill
Bill you win the gold star today! While I go home with my tail between my legs. You are 100% correct BAD ECM! I did have a 8747 ecm.
One last question. Why does 8747 ecm not run with a painless harness? I thought the only difference was no knock sensor.
I can't thank you guys enough
Thank you Jim and Bill
Bill you win the gold star today! While I go home with my tail between my legs. You are 100% correct BAD ECM! I did have a 8747 ecm.
One last question. Why does 8747 ecm not run with a painless harness? I thought the only difference was no knock sensor.
I can't thank you guys enough
03-24-2011, 03:38 PM
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Re: K5 TBI conversion idle issues (WINALDL)
You could make it run with the 8747. Just compare the ecm pin out diagrams.
Removing pins from the ecm connectors are pretty easy.
I run an 8746 car ecm in my Scout. I run the IAC in a caprice air cleaner.
But I run a 7747 ecm.
That way I can at any time, swap in either ecm to get me home if I should ever burn one up.
I haven't compared the wiring on the 8747 but I would bet it's close if not the same.
But the pick and pull JY is pretty cheap so a V8 7747 could be had for as little as $10.
Removing pins from the ecm connectors are pretty easy.
I run an 8746 car ecm in my Scout. I run the IAC in a caprice air cleaner.
But I run a 7747 ecm.
That way I can at any time, swap in either ecm to get me home if I should ever burn one up.
I haven't compared the wiring on the 8747 but I would bet it's close if not the same.
But the pick and pull JY is pretty cheap so a V8 7747 could be had for as little as $10.
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