cegha

TL;DR

Terrible rough idle conditions. Seeing codes P0340, P0345, P0011, & P0022. Replaced alternator with new 200amp Powermaster HO. Replaced VCT solenoids. Acted fine, and now back to rough idle issues, though much less severe sounding than previously.

Hello guys I'm looking for some direction of where to go from here with some issues going on.

First, details. 2008 Mustang GT (5 Speed). 62,699 miles. Only mod is C&L CAI + 93 Oct tune. Last oil change was 3-8-18 @ 61,401. Today is 6-8-18 @ 62,699. Only oil ever used after Ford is Mobil 1 with Mobil 1 filter.

Backstory, I've owned car since day 1 brand new off the lot. Pretty meticulous with my car care. So regular oil changes, yearly fuel filter changes, etc.

About 4-5 weeks ago I was leaving a store started my car & as soon as it started I heard a horrendous scraping sound of metal to metal contact. After it was started it was fine & I got it home. One of my really good friends is a Mercedes tech so he has tons of tools. We diagnosed it as starter not disengaging properly, because it would start turn over, then when you release the key is when it would grind. So 10 years, 63K miles (99% of which are short drives) I figure is about normal to above average life for that. Grabbed a new starter off rockauto (Remy Gold brand) & he put it in for me. No problems fired up, no grinding.

Same day. I drive back from his house to mine (15 minute drive) leave car for 5ish hours. Go back out to another friends house about 15-20 minutes away, all fine. Leave said friends house around 10:30PM. No traffic out that late since it was a week night, most lights are green all the way except the one to turn into my neighborhood. Slow down for the last light, and coming to a idle my car just goes to total ****. Incredibly rough idle, entire car shaking like there is no motor mounts, I knew timing had to be off, & spazzed. No one was around so I just made a left through the light & got home ASAP.

Next day I spend forum searching trying to figure this out. Some people said Throttle Position Sensors can sometimes go bad & to try cleaning MAF sensor. Cleaned MAF, then go down to O'Reilly & grab a TPS to try. I had bad luck getting the original off and destroyed it, so I had to keep the one I bought which was not the issue.

After this it finally dawned on me that I have a tuner and I could check codes. So let's see what we got.

I was seeing the P0340 & P0345 codes. More forum hunting said these could be cam phaser issues (unlikely) or alternator issues (more likely). So I looked through some alternator reviews and 10 years, 60-70K miles seems about the average for these OEM alternators, on top of that I have a aftermarket subwoofer and speakers in the car, so while I did spec it to not strain that OEM alt too much, it is still more than it was designed for. So drop a new HO 200Amp Powermaster in the car & upgraded the power wire to 4 gauge. Still no dice. I had to remove throttle body to get to alternator so that was cleaned out as well while it was off. I was now getting a new code P0022, Cam Position - Over Retard.

Then I stumbled on the holy grail. Apparently 4.6L & 5.4L 3Vs are known for VCT solenoids going bad and sticking. After watching some videos and fordtechamaloo (sp?) I was 99% sure this was the issue. Firstly, my friend even confirmed, when you rev it the issue goes away, it's only idle/lower RPMs that give issues, and the P0022 code pretty much confirms it's getting stuck open. Then I tried unplugging both VCT solenoids harness & it would idle fine & even drove it down my street and back.

I was also really pissed that I had to pull valve covers to change these. For reference since it took a TON of looking to confirm, 2005 - mid 2007 had off centered VCT solenoids that can be changed without pulling valve covers. mid 2007 - 2010 you HAVE to pull valve covers, the VCT solenoid is centered & you can't access the torx screw.

Fast forward through parts ordering from Tasca, I got new valve cover gaskets, VCT Solenoid gaskets, & 2 VCT solenoids. Day before last he came over & we busted it out much quicker than I anticipated. Get everything put back together, fire it up, let it run for like 15 minutes just chilling, looking for any leaks, & generally double checking all connections. Then once up to temp, rev on it a couple times up to 5-5.5K, comes back down to idle perfectly, & everything is gravy. Don't need to go anywhere that day so I just shut off the car.

Yesterday, I get ready to go somewhere & was still kind of skeptical. My friend is a bit of a fast worker & I wanted to make sure after sitting that no leaks developed. So I started it up to let it idle while I looked around under the hood for a few. Give it about 10 mins to come up to temp, rev on it a bit, comes back to idle just fine like day before. So probably 15 minutes of time at this point. Back out driveway and leave. Get to first stop light, all is well, slow down come to idle. Turn out and go, get to 2nd stop light which is probably another 8 minutes away from the first. Upon slowing down it was wanting to start the rough idle but didn't go into it near as bad as it was before changing VCT solenoids.

I turned around and took it back to the house, & had to rev it to 2K+ rpm to keep it from rough idling at stop lights. One thing I noticed, the 2 stop lights I had to make it back through, it was very sluggish to take off, almost like the VCTs were sticking shut and not opening, where as the old original ones would ONLY get stuck open & have idle issues, I defintely had idle & takeoff issues.

The P0340 & P0345 codes are still triggering along with P0022. I think before changing them I also got P0011 as well. While now I only get P0022.

I think the P0022 is causing the P0340 & P0345 codes.

So from a non code perspective what it acts like when you take it out of gear the RPMs seem to fall REALLY fast. I haven't paid attention to how quickly they dropped before, but I don't think it was this quick. Then the RPMs drop super low like down to under 500 before the engine decides oh hey that's not right, idle is 800RPM & it then kicks them back up to about 1K then adjusts back to 800, but when it drops down to 300-500 RPM that's when it kicks on the rough idle & the CEL will sometimes trip. Weirdly enough, when parked, once it dropped and started the first bit of weird idle noise, if you revved it to 5K and let it drop back it would catch properly at 800RPM.

The fast RPM drop seemed like it was only happening when coasting to a stop after taking the car out of gear. They seem to drop normally if you just rev it in neutral. 2005+ doesn't have a IAC from what I've read, so I've ruled this out.

This rough idle issue ONLY seems to start once car is up to temp for 30+ minutes. Used tuner to look at coolant temp. It was at like 195F I believe. It was 190 something, so pretty sure there are no over heating issues with anything.

I'm thinking the VCT solenoids were defintely on there way out. I inspected them & no screens were missing off of them, so there aren't any screens floating around in the engine. What controls catching the engine when your RPMs drop back to idle? It runs perfect sitting in neutral and revving it comes perfectly back to 800RPM. It seems like when driving for some reason they're dropping too fast & whatever is suppose to catch it isn't, causing maybe a temporary short from not enough power being generated by alternator at 500RPM or less?

The car seems about 80% better, but it's still not driveable. The only issue I had with the car previous to this I took to a Ford dealership & got screwed over. I REALLY don't want to take it to Ford again.

Next Steps: The only thing touching VCT solenoids is the oil. I don't know why only a roughly 1K mile mobil 1 oil would cause them to stick, but that could be why the others were sticking. My Mercedes friends said he would get me some stuff from work called BG. I won't know until I see it but I think it's bgprod.com stuff. Can anyone give any input on this being a good or bad idea? He confirmed for me it's Bg109 BG Engine Performance Restoration. I have never run any engine cleaners before, only Lucas fuel system cleaners about twice per oil change interval. Could it be sludge buildup?

From what he told me it's a 4 stage kit. You put the first container into your oil & let engine idle ONLY. He said the first item is suppose to break down all oil and sludge in your engine, which makes it not the proper weight anymore so you don't want to rev it or drive it, then you drain it. Then he said you put new oil and filter on & add another agent into the oil that you leave in.

Then he said there are 2 cans of stuff that you put in the fuel system that should clean that out.

I found this guide:
http://www.allfordmustangs.com/forum...ing-issue.html

Talks about complete diagnostic testing of VCT solenoids. I thought about maybe working through that as well. Seeing if anything turns up.

Put stock airbox back on and flash back to stock? I don't think CAI & tune is causing this after 10 years of being on. Also I don't think it's bad gas. I only use Shell 93, which I have for a LONG time.

Just really not sure where to go from here, since it definitely seemed fixed, & I feel the VCT solenoids were a part of the issue.

cegha

Update time.

I came across this video.


Basically where I'm at. Timing is assumed to be ok, VCT solenoids replaced, still random intermittent rough idle, noting when HOT.

This guy ended up having low oil pressure from a bad oil pump.

I thought this would be a good next thing to measure.

Didn't want to take it to dealership, but caved & just did it for 1 hour diagnose to see what they wanted to claim. Mentioned to have them check and verify oil pressure.

Got a call back from an official Ford dealership, and talked to the tech himself. He literally told me, aw hell man you just need a whole new engine, you could be chasin all kinds of problems & I could diagnose all kinds of random things and replace all kinds of random parts, but at the end of the day your better off just replacing the whole engine. He wrote up an entire quote that I may post here, just because of how ridiculous the whole thing is. I told them to nicely pound sand. I ended up asking if he checked oil pressure, I have no idea when, where, or how he took that measurement, but he claimed he saw 13psi.

Doing reading on VCT solenoids & proper oil pressures. It looks like the VCT solenoids REALLY like to have a solid 20-30psi. Maybe they could even handle dipping to 17psi. But I think once you get to 15psi or below especially on that far passenger side of the engine they start to become a bit unhappy. For record, I have not triggered any dash light that claims low oil pressure, if anyone can chime in on the number that triggers that light.

So I started looking into the OEM oil pump. Found the video below.


OEM looks like a fairly crappy/cheap oil pump tbh. I'm sure the stock oil pump on stock 5w-20 oil at a hot idle does not maintain 30psi. I'm willing to bet it's 20-25psi. Willing to bet closer to 20-22. That video shows how much pressure is lost on the OEM. I think almost all aftermarket cast iron backplate oil pumps flow 20-30% more at idle. So being such a small tolerance window to maintain proper pressure for the VCT solenoids, when that oil pump even THINKS about going south the issues rear themselves real quick.

I think AT A MINIMUM, i'm looking at a new oil pump. Luckily, right down the road from the Ford dealership is a local Mustang/Ford only shop. I called them the day before & talked to them, & went and dropped it off there today.

They want to monitor cam, phasers, vct, and oil pressure data, then he said he may want to pull valve covers and inspect the cam phasers depending what he sees.

They mentioned on some 5.4L they have sometimes seen the plastic timing chain guides break or chip falling down in the oil pan blocking the oil uptake screen. They said if we start taking apart the motor they should be able to tell firstly based on engine cover being off & being able to see the chain guides.

So I think to get to the bottom of the problem, the engine is going to need to be pulled, front timing cover removed, might as well inspect timing chain, cam phasers, replace oil pump, drop oil pan, check oil uptake screen, replace oil uptake with aftermarket oil uptake that comes with new oil pump, the chain guides can be checked for cracks or damage, primary chain tensioners probably need to be replaced.

I read if PCT seals fail or leak it can cause oil pressure problems. I believe 4.6L 3V has crappy plastic ones that are known to give out. I see there are official Ford cast iron ones that are nicer, & MMR also has some nice billet ones for slightly more than the Fords. I also noticed MMR has nice billet chain guides. Would it be worth switching to those from the stock plastic ones? With as much stuff that will probably need to come apart, I want to make sure to replace anything that could be problematic in the future.

So I guess best advise before getting to far into any mechanical issues. ALWAYS check your oil pressure specifically whenever a random ticking or engine problem to rule that out, or in my case, help out. I think a part of this project will also involve installing a oil pressure gauge in the car to keep an eye on for the future.

Coosawjack

According to my gauge on my 2014 GT my HOT oil pressure at idle is 10-12 PSI and it runs PERFECTLY!!

So why is it imperative to have higher pressure at idle??

flash_xx

The 4.6 3v and the 5.0 in your car are completely different engines.

cegha

Exactly. Totally different engines. I've read numerous reports that these 4.6L 3Vs like 20-30 PSI of oil pressure at idle for the VCTs.

I will have an update tomorrow. Shop wants to pull valve covers and physically inspect the cam phasers. I don't think they're going to find anything wrong with those though. I think the next thing they're going to tell me is they want to pull the entire engine and then pull timing cover to inspect timing chain guides to see if they notice broken pieces & inspect oil uptake screen, & at that point I have to be pretty committed. Does anyone know what I would be a reasonable amount of hours for labor for pulling and reinstalling the engine. From preliminary talk with them they mentioned it may be around 22 hours & I thought that seemed a little steep.

Both the "Ford Tech" & independent shop have claimed they witnessed improper oil pressure levels. I'm betting at this point either broken tension chain guides in the oil pan plugging oil uptake screen, blown out/damaged primary chain tensioners or the seals, or beginning stage of failure of a oil pump.

bl817

you can inspect/RR the entire timing system and RR the oil pump with the engine in the car, no need to remove, just need to jack the engine up an inch or so to allow the oil pan to drop enough to remove the pickup. the gauges in the dash are not much more than dummy lights and aren't very accurate. need to get a good oil pressure reading. you can try changing to 5w-30 oil and see if that helps things. Im guessing a bad tensioner seal but IMHO if your going to open the engine up, you might as well replace everything, lifters, followers, phasers, chains, guides, oil pump (Melling one) and all gaskets, bolts ect. should run like a top once all that is done. I would also try an alternator for a 2010 GT, PA ones are hit and miss, much like most non Ford parts for these cars. good luck