Forum Replies Created
-
Replies
-
Read up on O2 and heated catalyst monitors, appears to be a bad 02 sensor.
Despite my AFR reading normal under idle and WOT operation the O2 voltage dancing back and forth between lean and rich. Reading it in real time I see voltage as low as .12 and as high as .68. Fuel trims don’t show any lean or rich conditions so I’m assuming one of the three O2 sensors are bad causing wacky readings. Could also be the exhaust leak. I’ll start with an exhaust flange repair kit and take it from there.
Took it out for a second spin after it cooled down and completed another drive cycle, heated catalyst, only a single fuel system monitor and low sensor voltage came up this time. None of all that extra stuff.
Could an exhaust leak at the flange before the cat cause these issues? Sometimes when I start the vehicle I can smell exhaust coming from directly under the cabin/front seats and given how bad the last 2 winters were I do believe the flange where the downpipe connects to the cat is rusted out and leaking.
I took automotive technology for a few semesters before giving it up for a factory job, my experience level leaves me at 8-10 starting out and with all the tools + tool box combined with the cost of my medication I opted out for a better starting rate and good insurance. If I recall correctly a leak would cause 02 sensors to to read incorrectly and therefore cause the PCM to adjust accordingly. Given the diagnostic information could this cause both of the issues with 02/Catalyst and fuel system sensors?
No fault codes stored in the ECU. For the majority of the drive my FT didn’t go above or below 6%, and AFR except for the one spike stayed at 14.77 with cruise on, 12.8 under WOT which is normal.
I apologize for asking this here, I realize this is a thread for techs to discuss among themselves but I don’t have the $$ for dealership. I was banned from one of the best forums for 3800 info due to disagreeing with a mod over the possibility of coolant getting into oil from the LIM gasket (I had to replace it a couple weeks back after a broken coolant elbow fell into the LIM trying to retrieve it). The mod who banned me is also a mod on 3800pro.com and everyone has quit replying to my posts since then so I have nowhere else to go.
Great… More issues. Hopefully someone can shed some light on this.
First things first. For some unknown reason the #3 cylinder O-Ring melted and got stuck in my LIM. It took so much force to remove the fuel rail that the injector pintle cap broke loose from the injector and my ride is stranded until tomorrow until I the GB Reman arrives in the mail.
I kept tearing it all down, got the rear valve cover replaced and started on the water pump. I assume one of the water pump bolts runs into an oil passage because one bolt had an oil coating on it. This same bolt ran into the coolant passage because coolant poured out of it.
After all was said and done the coolant that came out had a nice rainbow oil sheen on it. It either came from the bolt, me using the same funnel for oil changes that I use for filling coolant or something else entirely. I also noticed the oil that pools on the LIM bolts on these engines had straight water in it. There was a clear bead of water sitting right in the middle of this pool of oil covering the LIM bolt which gives me hope that it’s just condensation and not coolant.
So I’m planning on running a coolant pressure test when it’s all said and done just to ensure I don’t have anything else going on, do you guys think it would be a good idea to test the coolant for hydrocarbons to make sure I don’t have a blown head?
Good news, not coolant leak. I boogered the thermostat when I removed it replacing the intake gasket which is what threw the code. Replaced the thermostat and the code hasn’t come back. The misfire was from the O2 wire touching the #6 plug wire.
Bad news is I have a leak from the block rail. A very small one but a leak is a leak. Right where the rear head, LIM and block meet there is a very slow drip making it’s way down the block under the head and hitting the exhaust manifold.
I’m going to be replacing my water pump and rear valve cover on monday. Bearing is squealing something fierce and I put the wrong alternator bolt in the wrong spot and cracked my valve cover back in Feb when I installed the rocker arms and intake insert.
Plan is to clean the leak up with degreaser, spray the area leaking down with brake clean to remove any oil or dirt and use a popsicle stick to smudge some RTV into the gap that is dripping oil and leave it to sit over night, hopefully it’ll seal the small gap up and stop my leak.
Yay! Good ole check engine light.
Just got a check engine code tonight. PO128. The coolant isn’t reaching temperature fast enough. Ran diagnostics through Torque.
MID:$61 TID:S1a
Heated Catalyst Monitor Bank 1
Min: 4,177 Max: 1
Current: 6,751MID:$a7 TID:$0b
Misfire on Cylinder 6, 1 count over the last 10 drive cycles.MID:$c8 TID:$30
No identifying info, so I’m not sure what this one is.
Min: 5,641.7 Max 409.6
Current: 2893.1Not going to be driving until I put in new gasket Saturday. Looks like I get to drive the Dakota.
Welp I feel like an idiot. After setting down the LIM I quickly yanked it off to apply more RTV just to be safe, didn’t check the gasket to see if they had shifted any. Now I’ve got an oil sheen in my overflow tank and my dipstick and exhaust smells sweet.
I’ll be re-doing the job on Saturday. Anyone have any bright ideas on how to flush the cooling system at home with household products so I can save some money after buying 2 gasket sets? 😳
I’ve checked after every drive, none so far. Hopefully it’ll hold. Thank god these things require RTV or I’d be digging into the engine again.
Yep they’re shaped like an upside down L. The flange was supposed to go inside the block, not outside. It doesn’t appear to be leaking so I should be ok.
She’s rebuilt and back on the road!!. Honestly it was easier than I expected, the hardest part was removing the brake line from the lever on the rear of the caliper itself. :woohoo:
Technically not fully rebuilt. Since the seals were the only issue all I did was replace the inner seal and the boot itself and slapped her back together, bled the brakes and everything is back to normal.
If I feel up to a challenge I’ll get some snap ring pliers and put the new springs in.
I did have an odd issue this morning however. Upon leaving work my car lights dimly blinked on and off repeatedly when hit the unlock button. Battery didn’t even have enough juice to turn the lights on afterwards. I know on these newer cars all sorts of funky crap happens when the volts drop too low. Got a jump, she immediately charged up however a relay started making a god awful buzzing noise followed by a brief burnt smell.
I noticed immediately my auto on/off headlights weren’t operating properly and turning the high beams on with the switch in this position yielded no results. I had wallyworld run a diagnostic on the charging system and battery and the battery was reading 518CCA out of 650 and normal charging system status.
Immediately suspected the cabin air temperature sensor due to being told “it could create other electrical gremlins” if I didn’t have it replaced and took it home and finally gathered the balls to pop the lower dash loose and take the metal bracket out. Pulled the sensor from under the dashboard and it was clogged with dust so I blew it all out. The buzzing noise was actually the sensor itself vibrating from all the dust collected on the fan which sucks air in over the temperature sensor/wire. “Buzzing” went away so I reinstalled. Figured from the brief burnt smell and the headlight issue I burnt a relay out.
Got called in to work as soon as I finished up the seal replacement to cover someones shift who fell and busted their butt and was rather crabby about it due the lack of sleep and being rushed to finish up the caliper job. Got off work at 10 and hopped in the car and now the lights are working properly again however the door locking actuator isn’t unlocking the door so one issue resolved itself and another came up. Gonna have to pop that door panel off and replace the actuator assembly.
Car has 88k on it. I’m going to be rebuilding the caliper.
6.99 and a colorful assortment of cuss words for the rebuild kit vs 79.99 for a new caliper.
I got the guide pin issue fixed, what’s going on now is the boot/seal that wraps around the piston and pulls it back Into the housing has come loose from the piston which is why my caliper piston won’t retract.
Well I got off the interstate after work yesterday morning and smelled a god awful burning smell, smelled just like a fried circuit board.
Took the driver rear wheel off and found the issue. I don’t know how I missed it earlier when I took everything apart but somehow the dust boot has popped loose from it groove in the piston itself which would explain why I have slack in my parking brake pedal and why the piston keeps getting stuck.
I went to Oreilly’s and ordered a rebuilt kit for $7 and I’m going to rebuild that caliper on Friday, I have a buddy coming over to assist me with that and bleeding the brakes afterwards.
I’ve never rebuilt a caliper, let alone a rear one and I’m wondering if there’s any special steps I need to take or if I just have to unhook the parking brake cable, use compressed air to pop the piston out and rebuild everything.
After driving to and from work with no brake pull or overheating driver rear caliper I’ve narrowed it down to either a sticking or faulty brake cable. It seems the caliper only sticks if I’ve applied the parking brake in the very recent past. It takes a while for it to fully retract.
Just got home from night shift so I’ll check those cables out later.
I’m guessing it was caused by the sticking caliper pin.
Well, they replaced the rear hardware for that side with the slide due to some kind of freak defect. Driver rear pads had taper on both top and bottom, so the pads weren’t making full contact. Got it all back together and took it for a test drive, stops just the same as it did so no worry there. I also put in neutral and pushed from the front and rear with all my weight behind it and it won’t budge, however the parking brake pedal still goes down was far as the design will allow when beforehand when before it would click 3-4 times and couldn’t get it go any farther.
I also checked both rears and the driver side (the one with the screwed up guide pin) and that particular rotor was putting off more heat than the other side. I also noticed at times the vehicle pulled to the driver side upon braking but only happened when I was on the left side of the road crown.. I’m back to stuck caliper piston at this point. When it first pulled the caliper off as shown in the photos the driver rear caliper was extended noticeably more than the passenger side. I’ve also read incorrectly adjusted parking brakes can cause a piston to stick. The only thing that is off is if this issue has been going on for a while why has my rotor not warped or pads cracked/glazed over?
From what I can gather online and from looking at the caliper itself the adjustment is either done under the vehicle, under the center console, under the carpet near the parking brake pedal itself or I noticed a nut wrapped around by a spring that seemed to tension the parking brake cable as it entered the caliper.
Anyone care to hypothesize what the issue could be despite the fact I could fully rotate the driver rear caliper piston back into place?
I also completely flushed my brake fluid (pushed over a half gallon through the system) last fall and I noticed my brake fluid reservoir is full of dark fluid already…