You have found out the hard way that some people who call themselves mechanics or technicians or whatever - should not be working on cars at all.


Follow these instructions I gave you before and report - or ask any questions that you need in order to follow the instructions.


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Taking the fan off on a Blazer requires some special equipment to hold the pulley while the water pump shaft is turned and is definitely not worth it just to find TDC#1.

It's really not that difficult from below. Just go buy whatever socket and length extension or adapter that you need to get on the crank pulley bolt from in front of the pulley (and behind the radiator shroud). What you buy needs to fit a 1/2" ratchet or breaker bar since the engine will be very difficult to turn with a 3/8 drive ratchet. If I remember correctly my setup is a deep 5/8 socket (3/8 drive) with a 1/2" to 3/8" adapter and a 1/2" ratchet - fits just right for me.

Yes, you turn clockwise as you are standing in front of the vehicle (like you was tightening the pulley bolt). It takes two revolutions of the crankshaft on a four stroke engine to go through the full cycle. Doesn't matter how many cylinders.

Especially if you are inexperienced, don't stick screwdrivers or anything in the cylinder. Too easy to munch that aluminum piston.

The easy way to turn the engine is with the starter, but you can't use the starter 100%. Have you buddy tap the starter a little at a time (and I mean as small of taps as you can) while you hold your finger over #1 spark plug hole. When it just starts to blow air past your finger, know you are coming up on TDC#1 so stop immediately and don't use the starter anymore. Now turn the engine clockwise with your 1/2" ratchet of breaker bar from below while you buddy watches the 2 timing marks on the pulley. One should end up about 5:30 and the other should line up exactly with the mark on the timing cover.

Drop the distributor in all the way with the rotor pointing to the #6 cast in the top, lock the distributor down, and you are good to go except for cam retard. Certainly it should start and run without SES light even if cam retard isn't set. But if you are not going to set cam retard, then don't modify the distributor hold down clamp. If distributor won't drop down all the way, turn the oil pump shaft to a slightly different position with a BIG and LONG screwdriver until it does.

Distributor does not hold any compression or pressure. You are just hearing air escaping past the piston rings.

As I told you before, Car Gauge Pro for Android along with the BAFX OBD2 Adapter (Amazon) is about $30. This will display cam sensor retard if you want to set it. Use the CMP Retard PID denoted with ** (double astericks). If you are an iPhone user - I believe you can do something with Dash Commander from Palmer Performance (they make an iPhone version) usng a WIFI OBD2 adapter, but know I have only tested Dash Commander for Android using Bluetooth OBD2.

 

What's with the condescending attitude? I know how to read. Clearly there is a misunderstanding here: you obviously understand the procedure, but the people around where I live do not. So I have to argue with people around here because they are clueless.

Anyway, here's what happened. After trying to get it all aligned, couldn't get it perfectly aligned. I didn't have the tools to modify the bolt position. Put it all back together and it didn't start. Eventually got it towed to a shop.

What to guess how the shop handled it? I explained to them what was going on and what I needed done (modify the bolt position and carry out the cam retard position procedure). 2.5hours of labour later, they told me that we were 180* off on installing so they got it to work. But then they told me that they could only get it in at 20* off. I told them that's why they need to modify where the bolt ties it down. They insisted they needed several mores hours to reinstall the old distributor and test to see in the timing chain is lose. They consistently treated me like I was retarded for wanting to change the distributor at all, and couldn't understand why I thought it needed to be changed (gee, like a lot of gear play and corroded connectors isn't enough of a reason). They insisted that the new distributor was some cheap brand (it was a Skip White), and that it must have been defective because it's not OEM.

Basically this shop already had me at $250, and wanted $100s more just to do everything other than changing the damn tie down position like I asked them to. Now my blazer has better acceleration, but it's completely negated by the fact that it's 20* off and I have a constant engine code now.

So let's recap: $130 for distributor + $320 for mechanics = $450 and it's still not installed properly. I'm looking into options to just sell this POS blazer

 

if you lived closer , I could fix it for free in twenty minutes

 

Duplicate deleted

 

Advice given here is typically for people who do things themselves. We try to help provide the knowledge. Since this is the Internet, you need to supply any necessary tools and actually do the work. If you admittedly opt to take your vehicle to someone who doesn't know how to work on it, don't blame us or the vehicle for a bad outcome. If it runs good now with no SES light, and you can't get the CMP retard set - then just drive it. I really doubt if cmp retard is 20 - probably they are trying to read timing advance at idle. But there is no way for us to know. If you want to find someone that knows how to set your cmp retard and has the tools just stop by your nearest local GM dealership and pay for the expertise.

 

Hi Les,

I'm trying to get a CMPRET reading on my 96 Yukon 5.7l Vortec.

I have a chinese ELM 327 Mini interface (had it for 5 years) and Torque Pro on an android phone. This kit works for a LOT of parameters, but I can't get it to work with a custom PID set up as described on
https://torque-bhp.com/forums/?wpfor...topic&t=5579.0.

I tried with Header: Blank, Auto, and also 6C10F1. I set the display to 3 decimal places; it never budges from 0.000. I used the Test function within PID Edit to test the PID, but it only gives a No Response code. I made sure the engine was held over 1000rpms before starting the app on the phone.

Have you made any progress on this front with Torque Pro?

I have seen your recommendation for Car Gauge Pro with BAFX Amazon interface. I guess I could spend the $40 for that kit and try it, but maybe you could share whether you think it would work as well on a 96 Yukon as it does on a Blazer before I go that route.

I appreciate any tips you might provide. I bought this Yukon new in 96. It is not throwing a code. However, I have done the intake manifold gasket job and also replaced the cap and rotor once. Now I'm doing another tune-up, including cap and rotor, and at 230K miles and 20 yrs of service, I'd like to check the CMPRET value and adjust if necessary.

Thanks!

 

I had same experience with Torque Pro - read zero no matter what. Never resolved it, but never really tried much as I have 4 other softwares that will read CMPRET if I have the need (2 Android and 2 Windows).

Turns out that Car Gauge Pro apparently does not connect to 1996-1997 Blazers for displaying any extended GM PIDs - only the most basic PIDs are supported in generic mode for those two years. I suspect that will be the case for a 1996 Yukon as well. Your experience may vary. However, Car Gauge Pro has been shown to work well for 1998 up Blazers. It is $8.95 and uses the same Bluetooth interface as Torque Pro.

The one I found that seems to work for all years of Blazers (including 1996/1997) is an Android App from Palmer Software (makers of Scan XL Pro) named Dash Command. It's $10 + you need to buy the extended GM PIDs for an additional $10, once you have the program installed. It also uses the same Bluetooth interface as Torque Pro. That's the one that I recommend for your 1996 Yukon. You can use your existing Bluetooth OBD2 adapter if it is connecting for Torque Pro. Only advantage of the BAFX OBD2 adapter is speed.

Good luck. If you need further help please be sure to start your own thread.

Les

 

I got it to work with DashCommand.

$9.95 for the app. $9.95 for the special GM PID's.

It works fine with my 5yr old chinese ELM327 Mini bluetooth interface.

I found an old thread on the palmerperfomance.com forum. It tells how to use the free evaluation version of DashCommand to see whether the app will support the Camshaft Retard Offset PID (aka CMP, aka Cam Retard) for your specific vehicle.

That's how I started. I installed the free DC app, then entered the basic details for my vehicle, then the following steps:
1.) Go to the Data Grid View.
2.) Tap PIDs.
3.) Tap Add PIDs
4.) Tap the little 3-dot menu button at the bottom right.
5.) Tap Sort PIDs.
6.) Sort by Manufacurer.
7.) Tap GM.
8.) Look for the GM.ENGINE.CR pid. If it is present in the list of available PID's under the GM heading, then supposedly DashCommand will display that value after you buy the app and the extended code set. If this particular PID is not present in the list, then there is no reason for you to buy the app, because the app doesn't support that code for your vehicle.

For me - it was the 3rd item in the list. So I bought the app, then I bought the extended GM code set.

Then I clicked the Gauges item in the home menu, and repeated a similar "sort by manufacturer" process to add the PID from the extended set to the main app. Then I set up a CR dial gauge with digital window, right next to a similar gauge for RPM. Then I started my Yukon and tapped the Connect button. Holy ****! There it was! -4.8°.

I tapped the back button and then the disconnect button.

Then I changed all my plugs, wires, my distributor cap, and rotor. While the cap was off, I loosened the distributor hold-down bolt, to where the distributor was free to turn, but snug, not sloppy. Then I put everything back together and set the distributor close to where it was before I started the job (based on a cell-phone pic). Then I started the engine (air intake assy still off the vehicle). I opened the throttle slightly by hand and stuck a thin piece of cardboard between the throttle-stop screw and its related contact arm on the throttle pulley assy and then let it shut on the cardboard, pinching it in place. This caused the motor to run at 1500rpm. Then I tapped the Connect button on the DC app, and pulled up my gauge screen. -9.4°

What I learned at this point was that the motor will start if your distributor is 7.4° out of spec, and also that it won't necessarily throw a code right away, because the only codes I got were MAF codes related to the fact that the MAF sensor was unplugged and laying on the floor across the garage.

Anyway, I twisted the distributor CCW, and sure enough, the CR reading came around to with the 4° spec window. So I kind of eyeballed the position of the distributor that was close to 0°, then I shut off the motor, bellied up on some folded towels on the fan shroud, turned the distributor to where I thought it should go, and then commenced the battle of tightening that damn hold-down bolt while laying on the motor and holding the distributor in the position I thought it should be. I tightened the bolt just past snug, then fired up the motor and restarted DashCommand.

I got 0.1°. LOL. I never get lucky like that, but I did today.

That's it. I tightened the hold-down bolt to 25ft lbs, buttoned everything up and went for a spin. On the hwy, it was cruising at 55mph at ~1500 rpms, and I tapped the connect button on DC, and presto, I was holding a fluctuating CR value of between 0 and 0.1°. Job done.

It was weird in a way. I had to do a lot of reading to try to find something that might work, and then all of a sudden, there it was.

Motor sounds smooth. No more tiny stumble here and there. Maybe it was the new spark plug wires and cap and rotor. Maybe it was the CR. maybe it's both.

Thanks for the feedback here.

Funny to chase a code this hard for a 20yr old vehicle.

Oh, one more thing: Dash Command is pretty good, but it is not an intuitive interface. I'm do some webdev work. Intuitive processes are elemental to good design. DC is pretty powerful, but it's damn clunky. If I hadn't found that old thread about sorting by manufacturer to see a code that is otherwise not displayed anywhere, and if I hadn't figured out that you have to tap a little obscure menu button before you can do the search, then DC would have been a bust for me. It has lot's of bells and whistles, but it has no intuitive flow. Torque is a better design, but it ain't got no CMP.

Good luck!

 

FYI the PID for my 2001 in Dash Command is GM.ENGINE.CMP_RTRD and GM.ENGINE.CR does not appear at all! However I do believe the PID for your CMP Retard on a 1996 Yukon can certainly appear as GM.ENGINE.CR.


I have found that with this Android App software you certainly have to be careful about wide sweeping statements. Someone who read your post and did your tests might think Dash Command wouldn't support CMP retard on a different year vehicle. Just like I previously thought Car Gauge Pro supported 1996/97..............