BAustin's Extended Track - 06 SS/SC Donor - #157 Registered

[baustin]

Since I've prepared this week to have work on my goblin, I decided to also attack the rear brake calipers to get my parking brake working evenly. I can't actually find the thread/post right now but my passenger side solstice caliper only rotates the parking mechanism 50% of the travel and hits a hard stop. The driver side rotates 100% and then stops. I originally assumed this meant the passenger side had the issue, something wrong with the internals since adding washers to shorten the cable didn't make a difference. I disconnected the cables at the caliper and rotated the parking mechanism with pliers: passenger side was impossible to rotate beyond 50% and the driver side easily went to 100%.

I ordered a replacement passenger side caliper and went through replacing it and then found the new one did the exact same thing. On my workbench both new and old easily rotated the parking mechanism 100% with pliers. At this point I should've known what was going on but after being a little tired I didn't realize it. I then dissassembled the driver side and reattached it after everything checked out on my workbench the same as the passenger side calipers. When reinstalled it still rotated 100%. So I made sure to do a couple tests:

setup: both rear wheels off, subframe sitting on wood blocks, transmission in neutral, engine off, wife in the driver seat, brake fluid lines installed, parking brake cables disconnected

brake fluid clamping:
driver side caliper off, passenger side only: axle couldn't rotate
passenger side caliper off, driver side only: axle couldn't rotate

parking brake cable test:
driver side disconnected, passenger side pulled fully (50% rotation): couldn't rotate axle
passenger side disconnected, driver side pulled fully (100% rotation): axle still rotates

So what I've determined is that the driver side solstice brake caliper isn't properly actuating by the parking brake cable. I had initially though the passenger side stopping at 50% of its rotation range was the problem but instead the driver side rotating the full 100% of it's range is the bad thing. So I now need to return the newly purchased passenger side (18-B5051) and get the driver side (18-B5050). Oh well, the return should be easy but it means I spent some time learning and some time working on an already functioning brake.

 

[Rttoys]

Good to know. Thanks.

 

[Lonny]

I think this may be an adjustment problem.

The solstice parking brakes self adjust every time you pull the parking brake lever.

The way it works is by unscrewing a threaded shaft out of the piston every time you apply the parking brake.

Under normal operation, it unscrews until it takes most of the pad to rotor clearance out.

In your case, the piston that pushes against the brake pad is threaded onto the parking brake plunger to tight.

This is not allowing it to unscrew.

You may be able to push and hold the brake pedal and at the same time pull the parking brake really hard to get it to start moving.

Once it starts unscrewing you will need to let off the brake pedal and start repeatedly applying the parking brake until it self adjusts.

With this style of parking brake caliper, if you ever need to put new brake pads you can't push the piston back in.

You will have to put a spanner wrench into the two holes on the piston and spin the piston back down on the threads to give the pads enough clearance to fit back in.

 

[baustin]

You may be able to push and hold the brake pedal and at the same time pull the parking brake really hard to get it to start moving.

Once it starts unscrewing you will need to let off the brake pedal and start repeatedly applying the parking brake until it self adjusts.

I'll give this a try after work.

I did figure out how it worked since I had to get the piston back in after working on things on my workbench and testing one side off the rotor for brake pedal use. The passenger side was easy to get spread back to fit over the rotor/pads. The driver side was terrible to get the piston retracted: when I finally got it close enough to squeeze fit was when the internal of the piston sounded like it was rattling/hitting something. I'm afraid the piston wasn't remanufactured correctly but I'm not sure I have the tools to open it up and get it back together if needed.

 

[baustin]

Normal parking for me: while on the brakes, pull handbrake, then release brake pedal. I've done that a bunch of times over the past 1000+ miles and it didn't self adjust. I just haven't specifically tried pulling the handbrake repeatedly during that time.

 

[baustin]

I pulled off the driver side caliper and took a video of the parking brake mechanism being rotated and then compared that with the new caliper. Older caliper did move the piston normally with the brake pedal, just didn't move with the parking brake pull. If someone thinks I should be able to pull apart the old caliper and fix it instead of replacing, let me know. I have some tools but not a full garage, for example I don't have a press (just a vice).

 

[baustin]

3 files from VM Scanner, the two from 5/30/20 is with previous coil packs. #2 was 2nd start while in the garage, #3 was shortly after that. File from 6/6/20 is with new coil packs. All data was from 0mph in my garage, though I did vary the throttle a little. I'm not sure if the P300 code is going to come back with the new coil packs but I'm still seeing the slight # of misfires showing up.

 

[baustin]

Good news is that Auto Zone accepted the unneeded passenger side caliper for full refund (as expected) and they warranty returned the driver side caliper for full refund too. When originally assembling my goblin I had issues with the banjo bolt threads and had to get a caliper or 2 replaced. At the time 1 of the auto zone guys I talked with locally has a solstice and he had just dealt with replacing his rear calipers and recognized what I was holding. Fast forward to today when returning for refunds and I worked with the same guy. He said the reason he replaced his originally was because the parking brake mechanism failed... same function description I had of the piston moving with the pedal but nothing from the cable mechanism. He processed it as a warranty return, which makes sense, though I had forgotten these duralast calipers have lifetime warranty. In the end it all turned out nicely and the cost was my time but I sure learned more about the calipers I have and how to work with them best.

Also highly recommend a pair of hose clamp pliers, these made bleeding the brakes really easy after all the work. I do have the rubber hoses instead of stainless, not sure those with stainless hoses can use hose clamping pliers or not.

 

[baustin]

So the P0300 fix wasn't as simple as worn out coil packs. Things that I'm considering looking into: vacuum leaks, injector issues.

What I'm seeing happen:
Occasionally at idle I'll notice some surging, sometime cold start but also at stoplights/stopsigns when at full temp. At idle my engine will have misfires counted on all cylinders but the most on cylinder 3, then about half as many on 1 and 4, finally some on cylinder 2. As soon as you add throttle the misfires go away. If I don't idle the car for long, the P0300 remains pending, but if I check a couple things with it idling in the garage, it won't be long till P0300 comes back.

What I've got:
Stock LSJ setup, spark plugs replaced and new ones are .035" gaps, new coil packs (still have the old for now, just in case), ZZP shorty exhaust header, standard supercharged Goblin intake and air filter, EVAP system not part of the Goblin, stock upper O2 sensor (no wideband for now), O2 plug in the Goblin muffler pipe. There is carfax history on the donor I used showing that the timing belt (of course it's actually a chain) was replaced, the intake/exhaust valves replaced, engine valve guides checked/replaced; I think this means it broke the tensioner and remembered it was an interference engine (this was in 2015 and was repaired by a shop, hence the carfax entry). I couldn't drive the donor before disassembly due to it's wreck but it did sound a little rough, sounded better in the Goblin. I have modified the tune file with HP Tuners to fix the DTC codes for EVAP, lower O2 sensor, catalytic converter and it's heating but completely not touched the operation of the combustion tables or any timing.

Things I've considered:

• Is it possible that the timing is just slightly off? I replaced the timing chain tensioner but didn't pull the side cover to confirm the timing completely right, it didn't seem to move during my work but it could've been off previously.
• If timing is good, the the valve replacement that seems to have occurred might not be sealing perfectly at the valve seats?
• Vacuum leak from the intake path - there are multiple locations I'm just not sure which ones to focus on here.
• Google search says injectors for this engine sometimes stop being able to seal, which becomes similar to a vacuum leak.
• Possibly a faulty O2 sensor causing the engine to think it needs to adjust incorrectly?

Screen grab from the attached VCM Scanner file. This was a cold start +5 minutes, occasional throttle at varying %.

Any thoughts on where I should focus? I can grab specific data from HP Tuners but I'm completely new to the software, any pointers would be good. I'm sure I've missed something, I'm trying to write things down to reference later, or if someone more knowledgeable has suggestions.

I've pulled valve covers on cars and rebuilt a briggs and stratton mower engine somewhat but I haven't done a lot of car engine internal work but I like to learn.

 

[Rttoys]

It won’t show misfire off of idle. It may still have a misfire, but it is not “counted” via scan tool.

Since all 4 cylinders are misfiring, you’ll need to concentrate somewhere that controls all cylinders. I would start with a vacuum leak. Basically you have the vac for the power brakes, PCV/air intake and intake gaskets (I think there’s one more). I would go to the basics and take some spray brake or carb cleaner, start the engine and spray around this areas. If the engine changes rpm up or down, you have a leak.

I wouldn’t rule out cam timing and such, but start with the basics.

you also mentioned gaping the spark plugs. Platinum and uranium Plugs don't require gaping as you can damage the surface areas.

 

[baustin]

It won’t show misfire off of idle. It may still have a misfire, but it is not “counted” via scan tool.

Since all 4 cylinders are misfiring, you’ll need to concentrate somewhere that controls all cylinders. I would start with a vacuum leak. Basically you have the vac for the power brakes, PCV/air intake and intake gaskets (I think there’s one more). I would go to the basics and take some spray brake or carb cleaner, start the engine and spray around this areas. If the engine changes rpm up or down, you have a leak.

I wouldn’t rule out cam timing and such, but start with the basics.

you also mentioned gaping the spark plugs. Platinum and uranium Plugs don't require gaping as you can damage the surface areas.

I just was listing the spark gap value, I didn't set them. Just listed since the ecotecs have multiple values published, I went with what seemed normal for the stock LSJ engine.

Didn't know it wasn't counting misfires off idle, good to know. It doesn't feel like misfires above there though. I've had a Saturn that had a vacuum leak at the intake gasket and it stumbled more than I'm getting but still have the spray can from finding the leak location that time... I'll give that a try next. Good idea.

 

[Rttoys]

Can you get a “fuel trim” reading?
does the O2 fluxuate up and down regularly?

 

[Karter2026]

Un plug the MAF and run it see if that helps. I had one in my car give me fits. It was just dumb luck to un plug it while it was idling on 3 cyl. It cleared right up.

 

[baustin]

Which fuel trim are you meaning? It looks like there are short term and long term. This video also has the O2 voltage reports. I'm not sure what these values should be, let me know if something sticks out here. This is a couple sections of the 5 minute scanner file being played back so anyone can view it the same way I see it.

I'll have to check with the MAF unplugged. It's not running bad, the misfire at idle is not that significant to me, it does surge occasionally but overall it just sounds like a performance engine setup. Maybe mine is just barely not working right instead of as bad as some others have seen.

 

[Rttoys]

Looks like the engine was cold, which will give you awkward readings. Plus, when you hit the gas, you change peramiters, so it’s somewhat hard to tell. But, it didn’t have many current misfires, just history misfires.

Could you tell it was misfiring in that video?
fuel trim looked fine, to a tad rich, but nothing really stood out. I’ll watch it a few more times this evening, when I get in for the night.

 

[baustin]

Looks like the engine was cold, which will give you awkward readings. Plus, when you hit the gas, you change peramiters, so it’s somewhat hard to tell. But, it didn’t have many current misfires, just history misfires.

Could you tell it was misfiring in that video?
fuel trim looked fine, to a tad rich, but nothing really stood out. I’ll watch it a few more times this evening, when I get in for the night.

Yeah, it was the first start of the day. There was a brief section in that 5 min sitting in my garage that it stumbled a little bit. I'll do a phone video of the idle next time I do a scan. This video was just a screen recording from windows instead of the log file I posted from 6/12. In the video of the log I skipped through a couple sections just to not make it be a full 5 min video.

I don't know what I want to see for the fuel trims or O2 readings, haven't found a guide for that online yet. I appreciate the help.

 

[Rttoys]

O2 should be bouncing up and down all the time. 0 is lean to 999 rich. I would say “normal“ range at idle should be 400mv to 700 mv. You goose it on the road and you should stick at 999mv till you let off and/or it balances out.

STFT (short term fuel trim) is current “average“ of what you are seeing at the O2.
LTFT (long term fuel trim) is an average of what stft is doing. Gets real complicated how it gets its number, though.
fuel trim should be 0% + or - 24%.
- is lean
+ is rich

when you hit the gas at all, you change the ltft and stft “charts” and your reading will be all over The place. At idle is you best bet to diagnose most problems.

 

[baustin]

I've got a couple videos I'll be loading shortly but here's what I've seen today:

• I ran the engine with the MAF plugged in, then restarted after unplugging, again plugged it in, and then unplugged. The first start after changing the connector (plugged/unplugged) was terrible but generally the 2nd start after the change was as expected.
• When the MAF was plugged in, the current misfire count was increasing and resetting every 10 seconds (I think 10 second counts)
• When the MAF was unplugged, it never registered a misfire on the counter while running.
• The 2nd time I unplugged the MAF, it took 4 tries and managing the pedal/throttle to keep it idling. The 5th start was normal. I probably didn't cycle the key to off, just from on <-> start after it clunked out. the 5th start showed a couple current misfire counts but it didn't increase while running this time, seems like it was just a count of the clunking out. When I fully cycled the key and started again, the counter was at 0 and never increased.
• The first couple starts the engine was warming up but it was into the 170+ range by the time I plugged the MAF back in and remained warm for the final unplugged tests.
• The videos I took include some close ups near the exhaust to see if the misfire is audible, it's sure not significant to me but I don't really hear a difference between having the MAF plugged in or not.

Prior to the MAF checks, I ran the engine (with MAF plugged in), and checked around with a carb cleaner spray and tested a couple hoses and around the intake gasket area. There were no changes in the idle sound during these sprays.

I think this brings me to 2 questions:

1. Does the current misfire counter work as I'll shown in the video when the MAF is unplugged and the engine is at idle? I know it didn't count with the MAF plugged in and giving it throttle so I'm wondering if I didn't actually find a result.
2. If I can assume that the MAF being unplugged would still increase the counter, the MAF should be my problem. Is this likely cause the random misfire like I'm seeing? I can replace the MAF with a new one if it seems like the culprit here.

log files are attached, videos coming soon

 

[Ross]

I think you are running rich. The LTFT are near or sometimes maxed at -20% correction factor.
Do you have a wideband logging? I don't see one, but it would help.

 

[baustin]

One thing I've run across is that GM put out a service bulletin about lightweight flywheels causing the misfires, so I could possibly be chasing a ghost here.

https://www.cobaltss.net/forums/problems-service-maintenance-69/gm-pip4717-ecotec-misfire-dtcs-no-concern-found-190915/

Videos from today (I think I numbered these like the log files):