Bruce Amacker Posted June 24, 2011 Share Posted June 24, 2011 Thinking out loud here..... What are desired and actual ICP at this time? Have the injector o-rings been changed? Have you air tested the heads? When was the oil changed last? Perhaps ground the IPR idling with the VC off and look for leaks, it should build over 4Kpsi..... Have you driven it with a base oil pressure gauge on it? Good Luck! Quote Link to comment Share on other sites More sharing options...
Jeff_E Posted June 24, 2011 Share Posted June 24, 2011 Hotline had me block off both heads individually and record IPR readings at idle and 1500 rpm, then told me to replace the inj o-rings on the bank that had the highest IPR. When I blocked the right head, I got 11.7 at idle and 15.6 at 1500 rpm. When I blocked the left head, I got 11.7 at idle and 14.06 at 1500 rpm, so I proceeded to remove all 4 left bank injectors and I cant see any problems with the O rings. I've got another email in to hotline now. ON EDIT: closer inspection found 1 o-ring that was slightly deteriorated at the edge. I'll keep you guys posted whether or not it fixes it, if for no other reason than I'll be able to search for this thread next time I get one of these problem children in the door. Quote Link to comment Share on other sites More sharing options...
mchan68 Posted June 24, 2011 Author Share Posted June 24, 2011 Jeff, does yours have any driveability symptoms? Or does it just set the code like the vehicle in this original thread did? Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted June 24, 2011 Share Posted June 24, 2011 On a long shot if you still have the injectors out, run your finger into the holes and see if the injector o-rings have worn a groove into the cast iron injector holes. I've only seen this a couple of times with similar problems reported- leaking o-rings even when new. Diag is to run it with the VC off, ground the IPR, and look for leaks but this is a bitch on an E-van. Your Hotline test is accurate but still isn't checking for leaks at high ICP which is where your problem is. It's possible to have no leakage at 1500rpm (what's your ICP at this point, under 1500PSI, right?) but HAVE leakage at WOT/load where the desired ICP is 3000ish. Keep this in mind during your diag. Leaking injector O-rings is a huge pattern failure which could easily be your problem, even with the test results reported. IIRC your HPOP and IPR are both new. Did you try another ICP for S&G? I'm thinking the HPOP is starving for oil on the low end or the upper injector o-rings are leaking. What is your IPR at a hot idle? 9-11% is normal with both heads hooked up. I think someone on DTS used a Porto-Power to pressurize the head feeds (engine off) to identify hydraulic leaks (ICP). Let us know how you make out. Quote Link to comment Share on other sites More sharing options...
Jeff_E Posted June 25, 2011 Share Posted June 25, 2011 On a long shot if you still have the injectors out, run your finger into the holes and see if the injector o-rings have worn a groove into the cast iron injector holes. I've only seen this a couple of times with similar problems reported- leaking o-rings even when new. Diag is to run it with the VC off, ground the IPR, and look for leaks but this is a bitch on an E-van. Ah crap, they are all back in, and by all, I mean all 8. After resealing all 4 in the left bank I road tested it and the problem persisted, even though the upper o-ring in #2 had deterioration that looked like a dummy plug o-ring in a 6.0, so I resealed all 4 on the right bank too, but those 4 all looked ok anyway. Before I put the right vc back on I let it run up to operating temp and then full fielded the IPR while jumping the starter with the key off. I didn't see anything abnormal, so I put the Right VC back on and road tested it - Still will set a mil with P1211 when accelerating over 75mph. It bogs down somewhat when it happens... A noticable lack of power, but still drivable enough to get back to the shop without anyone on the road thinking anything is wrong. Monday I will probably have to take the left VC back off and try full fielding the IPR to see if anything happens. Your Hotline test is accurate but still isn't checking for leaks at high ICP which is where your problem is. It's possible to have no leakage at 1500rpm (what's your ICP at this point, under 1500PSI, right?) but HAVE leakage at WOT/load where the desired ICP is 3000ish. Keep this in mind during your diag. Leaking injector O-rings is a huge pattern failure which could easily be your problem, even with the test results reported. Do you think it would be safe to full field the IPR with both valve covers off and the engine running? I'm a little hesitant to try, but I think you're right about it only leaking at very high ICP. The thing that worries me though is it doesn't do it right away. I have to drive it for a few miles before it will do this, so I'm wondering if maybe the HP reservior isn't being replenished fast enough. I never see the oil light come on, but I tried hooking up a low pressure oil gauge in to the reservior plug and noticed that pressure in the reservior does tend to drop to just about nothing under load. I don't know whether or not that's considered normal as there isn't a published spec for HP reservior pressure, and I haven't tried this on a known good truck. I'm almost starting to wonder if maybe there's something wrong with the LP pump or oil pickup tube??? IIRC your HPOP and IPR are both new. Did you try another ICP for S&G? I'm thinking the HPOP is starving for oil on the low end or the upper injector o-rings are leaking. What is your IPR at a hot idle? 9-11% is normal with both heads hooked up. The HPOP is brand new, the IPR is a swapped used one, the ICP is a brand new one on loan from our parts dept. Hot idle IPR is usually around 9.3% I think someone on DTS used a Porto-Power to pressurize the head feeds (engine off) to identify hydraulic leaks (ICP). Hmmmm... We have a porto-power... I wonder If I can adapt it to the icp fitting (thinking to myself). Let us know how you make out. I'm sure I'll have more to say on Monday about this. This is going to be one of those weekends when I don't sleep very well. I need to learn not to take my work home with me. Quote Link to comment Share on other sites More sharing options...
Brad Clayton Posted June 25, 2011 Share Posted June 25, 2011 I don't think I would go to work on Monday. Quote Link to comment Share on other sites More sharing options...
Jeff_E Posted June 25, 2011 Share Posted June 25, 2011 Oh believe me I don't wanna go back to this thing, but if I dont it will just be waiting for me Tuesday with an even more pissed customer. I gotta man up eventually, Monday is as good a day as any. Quote Link to comment Share on other sites More sharing options...
Brad Clayton Posted June 25, 2011 Share Posted June 25, 2011 No sir, I'm thinking it would be a good time to swing down and pick up Mr. Holekamp and all his EGR cores and personally deliver them to the guys in Arizona then hit up Vegas. That should get you out of the shop for a good week or two. That's plenty of time for some poor sap to get your problem child. Of course there may be a hit takin' out on you though. Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted June 25, 2011 Share Posted June 25, 2011 Hmmmm... We have a porto-power... I wonder If I can adapt it to the icp fitting (thinking to myself). Weatherhead 7897 is the adapter fitting to check the HP oil with a gauge at the head ports or do an air test. Thread is ½” NF with an o-ring, also known as 5/16” inverted male thread, any parts store or general hardware has it for $3, and you may have one in your toolbox- they came with reman master cylinders for GMs for decades. You will need to supply a gasket for the bottom of the fitting. I'm sure I'll have more to say on Monday about this. This is going to be one of those weekends when I don't sleep very well. I need to learn not to take my work home with me. Ain't gonna happen, dude. If you don't take your work home with you to some extent, you aren't a good tech. Originally Posted By: Jeff_E I have to drive it for a few miles before it will do this, so I'm wondering if maybe the HP reservoir isn't being replenished fast enough. I never see the oil light come on, but I tried hooking up a low pressure oil gauge in to the reservoir plug and noticed that pressure in the reservoir does tend to drop to just about nothing under load. I don't know whether or not that's considered normal as there isn't a published spec for HP reservoir pressure, and I haven't tried this on a known good truck. I'm almost starting to wonder if maybe there's something wrong with the LP pump or oil pickup tube??? HUH? The reservoir pressure is within a couple of PSI of main galley pressure. It sounds like your pickup tube screen is plugged up. Your problem is downstairs. The only time I've ever seen LPOP pressure go down as RPM went up is when the screen was restricted. Has the pan been changed, motor changed, or bottom of the pan pushed in from sitting on it? That's what the last one was. Put a gauge on the galley plug (left side of the block, or in the cooler???) and check what's going on. You're not gonna like what you see. I don't know if a borescope would help through the drain hole or dipstick hole in the rt side (there's a trick for that, ask if you need it.) Has any work been done with silicone lately (pan, VCG, covers, etc? using the wrong silicone WILL cause oil aeration even if it's brand new oil. BTDTGTTS Quote Link to comment Share on other sites More sharing options...
Jeff_E Posted June 25, 2011 Share Posted June 25, 2011 This is the first time this truck has been to my dealer, but I will definitely have a look at that oil pan on Monday. I'll stick the oil pressure gauge in the main oil galley and see whats going on there too. I would have thought the oil light would come on if there were a problem there, but now that I think about it, I suppose lube oil pressure could be high enough not to trip the light, but low enough to cause a problem feeding the reservoir. I think one of the other techs even has a borescope that would fit through the drain plug hole. Thanks Bruce, I was starting to run out of ideas Quote Link to comment Share on other sites More sharing options...
mchan68 Posted June 26, 2011 Author Share Posted June 26, 2011 You know, I just had an E-Series ex-ambulance rolling in on my doorstep a couple days prior to Jeff's posts in this thread. It was a '98 or something close to, with about 390,000 kms. on the ticker. This guy from another garage brought it to me, informing me that he had replaced the ICP sensor to repair what I vaguely recall was also a P1211 or P1212 unsuccessfully. He had asked me to scan the truck for him too, but unfortunately our VCM was broken at the time. Apparently the symptom was the truck would run and drive fine, but then would intermittently stall, but restart immediately with black smoke re-appearing momentarily. Upon looking under the truck, was when I noticed the oil pan was slightly crushed, at least enough that it was up against the oil pick-up. Jeff, is this the same symptom your truck has? And thanks by the way Bruce, for making me remember this truck with your suggestion to have Jeff look "downstairs" for his concern. Quote Link to comment Share on other sites More sharing options...
Jeff_E Posted June 26, 2011 Share Posted June 26, 2011 Mine doesn't stall, after driving for a few miles on the freeway and try to do a hard acceleration when you're already doing about 75mph it will bog down as the IPR ramps up to 65% and set a P1211. I did notice some injector ticking after this happens too. Quote Link to comment Share on other sites More sharing options...
Jeff_E Posted June 27, 2011 Share Posted June 27, 2011 well, this morning I moved the oil pressure gauge to the plug in the side of the filter housing and road tested it. My initial oil pressure on a cold start was 48 psi, but as it warmed up that number got lower. Under increased rpm, the gauge ticks upward initially, but then climbs downward. I was unable to view the screen section of the pickup tube through the drain plug, so the engine needs to come out and the oil pan needs to come off to see what's going on. I just gave the writer the bad news. I sense a shit storm coming... The likes of which I haven't seen in quite some time now. Stay tuned... Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted June 27, 2011 Share Posted June 27, 2011 Too bad they don't make shit umbrellas Quote Link to comment Share on other sites More sharing options...
Brad Clayton Posted June 27, 2011 Share Posted June 27, 2011 Quote Link to comment Share on other sites More sharing options...
Jeff_E Posted June 27, 2011 Share Posted June 27, 2011 Well, it wasn't so bad. The owner was pretty understanding, and today I found out another dealer has had the pan off of this truck 3 times prior in attempts to fix external oil leaks, so I'm pretty sure there's silicone plugging up the pickup tube, but the guy didn't want to put any more money in his truck today so we're giving him a discount on the parts and labor we have in it, and he seemed ok with that. I just feel unsatisfied that after all that effort I didn't accomplish much more than to drain a guys wallet. I keep telling myself next week will be better... We'll see. Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted June 28, 2011 Share Posted June 28, 2011 It's too bad there's no way to clean those damn things out with the pan on. I have seen guys cut the bottom of the pan out, clean the screen, and weld it back up. This kind of shit almost makes me want to do that..... Quote Link to comment Share on other sites More sharing options...
Jeff_E Posted June 28, 2011 Share Posted June 28, 2011 Yeah, and It would have been nice if the other dealer had done the oil pan reseal by the book (engine removal) instead of doing it in vehicle and letting who knows how much silicone loose in the pan. It would have saved the customer and myself a lot of time and money. Oh well, if nothing else we have added some depth to this thread so the next guy who does a search for P1211 on this site will have some more info. Would you look at the time... It's Beer:30 already. Thanks for the help fellas Quote Link to comment Share on other sites More sharing options...
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