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After getting the hood up (bad struts, broken latch linkage), I truly amired the beauty of this machinery. Then, after a long pause, I started looking at the details. Here's my first list to get her through inspection. I have some questions embedded in the list:
Driver's side wiper not moving, wiper arm knurls are gone. Tightened the nut, working for now, need a wiper arm or a way to knurl the current arm. I do have some thin copper sheeting with adhesive on one side. I may try a strip of that.
3 CELS, pics below. I think I should start with the Bank1 upstream sensor. Bank 1 is driver's side, 2 is passenger?
Could the O2 sensor affect the misfire or is that a separate issue?
This clutch at the top right of the serpentine belt is making some noise - what is it? Does this engage the supercharger, as in MadMax?
One of the lower idler pulleys for the serpentine, lower left midway down, is wobbling a little and I think I see a bit of rust. I need to find a diagram of those parts. I belong to a russian website that may have that tecnical information.
I don't like this mod. Will I take my life into my own hands if I remove this possible gang tag?
Gotta get the sub out of the trunk at some point. Stripped windshield wiper arm 3 codes, leaning toward replacing Bank1 Sensor1 Is that a good timing number? Certainly has a rough idle Noisy clutch - what does it control? Supercharger? Prior owner's mod. What is that little port that is missing the cover? What is it?
Address the misfire in cylinder 2 before spending money on anything else. Fixing other things won’t fix the misfire, and be a waste of time and money if it’s something you can’t fix.
Yes that clutch is for the supercharger…
misfire=rough idle
when you datalog what do your 02 sensors read? Are they rapidly jumping voltage from .1-.9v which is a good thing or are they slow to change or not changing which isn’t a good thing?
There’s a lot of research you can do on this thread and the internet on those specific fault codes but my best advice would be to really really thoroughly check for vacuum leaks. Take off both air boxes and check all the lines from the valve covers to behind/under and around your throttle body. Good luck
Address the misfire in cylinder 2 before spending money on anything else. Fixing other things won’t fix the misfire, and be a waste of time and money if it’s something you can’t fix.
Yep. I'm going to swap the spark plugs from one cylinder to another and see if the problem follows, then do likewise with the coil pack.
Yes that clutch is for the supercharger…
misfire=rough idle
when you datalog what do your 02 sensors read? Are they rapidly jumping voltage from .1-.9v which is a good thing or are they slow to change or not changing which isn’t a good thing?
There’s a lot of research you can do on this thread and the internet on those specific fault codes but my best advice would be to really really thoroughly check for vacuum leaks. Take off both air boxes and check all the lines from the valve covers to behind/under and around your throttle body. Good luck
Yep, there's a real good chance there's a vacuum leak. The previous owner put on a different non OEM cold air intake system, so there's a good chance something isn't right. On the O2 sensors, that bank one sensor one isn't moving at all. It's staying on zero.
Thanks to everyone who's contributed to my original post. I did remove the supercharger pulley so I cannot start the car until the new replacement bearing delivers.
Once I have the pulley and the serpentine belt back on, I will run the car and check for vacuum leaks. I will probably use a can of carburetor cleaner while monitoring the fuel trim levels and the O2 sensor response. Hopefully that will make any vacuum leaks show up quickly.
Having said that, has anyone put together a comprehensive list of the most common vacuum leaks in hierarchical order? I'm going to search some for such a list, of course, but someone may already know where to find that information.
If I can't find any vacuum leaks with this method, then I will probably pull the plugs and coil pack from cylinder 2 and swap them with another cylinder to see if the problem follows the components or stays with the cylinder. This will also give me an opportunity to inspect four of the spark plugs and measure two of the coils for DCR. I also have a spark tester that I can put in line and see what spark strength I have. I'll be sure to post pictures and results.
Any and all suggestions are welcome.
PS while reading through some forum posts, I realized that most of the time in my experience, when a vacuum leak is present, the idle usually goes up in RPM. My idle is good. It's just a little rough, I assume from the misfire and/or the non-functioning O2 sensor. Wouldn't that point the finger at spark plugs or coil pack more than vacuum? I know this is all speculation and I'll have to really get into hands-on diagnostics to find the problem, once the parts are in. I'm just trying to develop an efficient strategy for troubleshooting.
Last edited by tensleep80; Mar 28, 2023 at 04:21 AM.
A vacuum leak probably isn’t going to cause a specific cylinder misfire , I would go directly to that cylinder. Coil spark plugs wires injector compression. Most times it’s the coil, and hopefully that’s what it is. With 2 plugs per hole, having both go bad with a healthy cylinder isn’t too likely. That’s why I said sort that out before throwing money at it.
A vacuum leak probably isn’t going to cause a specific cylinder misfire , I would go directly to that cylinder. Coil spark plugs wires injector compression. Most times it’s the coil, and hopefully that’s what it is. With 2 plugs per hole, having both go bad with a healthy cylinder isn’t too likely. That’s why I said sort that out before throwing money at it.
I was wondering about that. Since there are two plugs, if one plug fouled or failed somehow, would it still report a misfire since the other plug is active? If so, I think my first move is to swap coils and see if the problem moves. Your thinking aligns with with mine; I think that a vacuum leak would probably have more random misfires reported.
I do trust others experience when they say to look for vacuum leak so I'm not going to take that lightly either. That will certainly be on the list of things to look for. It may not be causing a code, but that's no guarantee I don't have vacuum leaks on this old car.
Last edited by tensleep80; Mar 28, 2023 at 11:40 PM.
I may have some time to do a little work on the car this weekend. I am still waiting on the sc pulley bearing. It should come in Saturday night.
While I wait, I will change the compressor oil, since the pulleys and belts are off already. I'm going to wait on the water pump until I figure out the misfire first.
I will pull and inspect the plugs for cylinder 2 and measure the DCR for the coil pack. If all of that looks good, I'll exchange the parts with cylinder 1 and see if the code follows.
On another note, the carpet is ruined in this car. Someone thought it would be a good idea to install Dynamat. On top. Yes. On top of the carpet.I don't intend for this to be a show car at all, but I do need a good solution. Suggestions? Car mats will do for the short term. I do have the original mats, but they are in bad shape as well. Hopefully, some of the ganja aroma will leave with the carpet. I can deodorize the headliner, but I have to be very careful. That adhesive is old.
I would check for leaks out of the brake booster line(big thick grey line coming out of the back of sc snout) I would also check the Sai lines (secondary air injection lines) and check crankcase connectors. You might want to check out the 02 sensor that isn’t moving if nothing else works
I would check for leaks out of the brake booster line(big thick grey line coming out of the back of sc snout) I would also check the Sai lines (secondary air injection lines) and check crankcase connectors. You might want to check out the 02 sensor that isn’t moving if nothing else works
Thanks for the tips, I will check around more tomorrow.
Yesterday, I changed the compressor oil. The wind blew the spent oil in the measuring cup over. Now my portable work table smells like a barnyard.
So far:
Changed SC oil, 150 ml Mobile Jet Oil (stinky)
Changed SC bearing, NGK bearing
Changed idler pulley next to SC clutch
Changed hood strut cartridges
Reseated hood cable in hood release lever
Tightened ac compressor fittings and pulled a vacuum on the system
I drove the car a little and it is running a little worse today. I noticed oil smoke from around cylinder 2, the one that is misfiring. Tomorrow morning, I will get into that cylinder's issues a bit more.
Last edited by tensleep80; Apr 2, 2023 at 12:24 AM.
These plugs are out of cylinder two which is reporting a misfire code. My guess is either the wire wasn't seated correctly or there's a problem with the coil pack or the wire. I'm assuming, since it seems one of the plugs was firing, that the wire may be the culprit. It came off like all of the others. I have to find the procedure for measuring resistance now. I don't think the one on the left is firing.
I have an oil leak from the PCV cover. While cleaning off the grime, I noticed what I thought was a deposit but it actually is some pitting. What might have caused this? It doesn't look like a casting imperfection and I can't see that passing AMG's quality controls. Something must have been spilled at some point on this magnesium.
While I'm troubleshooting this misfire on cylinder 2, it's okay for me to run without this cover sealed, isn't it? I have to order the correct goop and I may go ahead and reseal the valve covers while I'm at it. What say you? Heavy pitting I will have to inspect this cover for cracks. Oil on the manifold. Wet coil packs underneath the PCV cover
Last edited by tensleep80; Apr 2, 2023 at 09:58 AM.
Reason: Grammar and spelling
Yeah, I didn't think so. This will allow for arcing, moisture and oil intrusion, etc. Coil packs, coil wires and plugs. Damn, that's a chunk of change.
Last edited by tensleep80; Apr 2, 2023 at 12:18 PM.
Hopefully for you it’s just that, and not something mechanical. That’s why I said it would be a primary goal to determine a misfire on a specific cylinder before proceeding to change fluids and such.
Hopefully for you it’s just that, and not something mechanical. That’s why I said it would be a primary goal to determine a misfire on a specific cylinder before proceeding to change fluids and such.
Yep, so far I have kept the costs to a minimum, just stuff that had to be replaced to really feel safe running the motor. I'll get the ignition sorted out.
Installed new coil packs, plugs and wires and the car is running much better. I also installed some new air filters. The previous owner had really botched up the air filters. One of them was facing backwards and the filters themselves are really deteriorated. Anyway, I got all that straightened out.
I do have some oil leaks to sort out. I'm going to order valve cover gaskets in the correct RTV sealant for the PCV covers. While looking around for the oil leak, I noticed that the belly pans are missing from this car. I'll have to see if I can find some at a junkyard later on down the road.
I think I'll jack up the car tomorrow and see if the O2 sensors just unplugged or if I can figure out what the problem is with that.
I sure am having fun though, this car is going to be amazing. The work I've done so far has made the car much quieter in the engine bay. I can hear the water pump softly knocking, asking for attention. I can also hear the power steering pump whining louder. I need to look into that tonight and see what's involved there.
New MAP code. I need to reseal the PCV cover because I took it off. I'm waiting for new sealant and valve cover gaskets. Could that cause the code? Cold air intake installed correctly All new ignition parts Old damaged air filter in backwards and new filter Old coil packs and new coil packs I'm getting started
Not so sure I’d call that a cold air intake, the filters are behind the radiator pulling hot air.
Actually it hooks into the two ports that are above and in front of the radiator, the original two ports for the original intake system which are located directly behind the grill. That is cold air coming from the front of the car. I thought it was junk at first and then I saw how it was routed and put it together right. It's actually a pretty good system for a cheap bolt on with no modifications. The key is understanding how the filters install and seal.
Last edited by tensleep80; Apr 8, 2023 at 10:26 AM.
I am going to lift the car for the first time and have a look around the bottom. The main goal is to evaluate the O2 sensor that is throwing the CEL. While there, I will do a coarse wipedown of the oil leaks and see if most of it is coming from the valve covers. I sure hope it isn't the rear main seal and/or the electrical connector housing to the transmission. I intend to service both of those, but I'd like to drive this car some before tackling those jobs. Pictures to follow.
Edit: well, I am pretty conviced that the sensor is kaput (see what I did there?) I am going to pull and replace it.
I am missing the back cover, but still have the front cover for the underside. When I lowered it, oil ran out. I had a good look and I think I am going to be lucky. The oil is coming from the passenger valve cover and the oil cooler/filter area. I have seals coming this week, so I may get into pulling and cleaning the valve covers and oil cooler today. I will have to seal up the openings carefully; several days may pass before I can finish the job.
Last edited by tensleep80; Apr 8, 2023 at 04:29 PM.
Reason: Adding to post
So I just finished working 50 hours of night shifts. I got off this morning at 6:30, went and got a tooth implant finished and started wrenching. I'm trying to seal up the oil leaks first. I've got the valve covers off and they are soaking. I think I'll wait to pull the oil cooler and oil filter housing until I get these covers back on. For what it's worth, the spark plug boot puller wrench fits the fuel line. Old shower curtains also make good rocker covers. Getting started First cover off Protection Second cover off protection Work bench with ignition parts Shade tree parts washer Screw organization
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
Crap
