04 4.7L V8 Misfiring on ALL cylinders after starter replacement

[4thGen4.7]

Hey everyone - My 04 4.7L v8 is having misfire on all cylinders, codes P300-P308. When I start it up, it will run for a few seconds until it dies. I was able to eventually start it up enough to where it would idle until I turned the key off. The idle is really, really rough though. No response to throttle (kills it), but when it revs up to 2k on start, it sounds perfect, it just gets rough when it comes back down to ~500-1k RPMs.

So, this started happening when I replaced the starter. I installed new gaskets for the lower manifold (didn't remove upper) - originally didn't swap injector o-rings and grommets, but when I ripped it apart to do it again after having issues, I used all new rubber.

One thing that did happen after I could get it to run for a bit was tons of smoke coming from passenger side cat, which has an O2 sensor I replaced about a year ago that hasn't given me any problems. It seems to have all burnt off though because there is no more smoke.

I built a DIY smoke machine and tested for vacuum leaks from the intake duct after the MAF, didn't see any leaks but there is a chance I couldn't get enough smoke past the throttle body flange, i'll be testing that again.

I cleaned MAF and throttle body.

I replaced all spark plugs. Nothing too bad with the old ones other than one with a lot of oil on it (I have leaky valve cover gaskets, going to swap those this weekend too)

I have a fuel pressure gauge but I either 1. don't know what tf I'm doing or 2. it is faulty, because I'm getting 0 pressure from the inline, despite hearing the pump come on and getting some fuel delivery. I want to spend more time on this this weekend.

One thing that could be cause for concern, because I lubed up the injector o rings and grommets, I have injectors that are easy to rotate in their spots, but no leaky injectors. How tight are these fuel rails supposed to be? No torque spec in Chilton manual.

I have noticed that when I crack open a banjo bolt on the crossover, or when I swapped the fuel pressure regulator that, even though fuel comes out, it doesn't seem to be as pressurized as it could be, given the volume that comes out.

I replaced PVC and PVC hose.

I'm really leaning towards it being a fuel delivery problem, but what are the chances that I could have dead fuel parts right when I fix a starter?

THANKS IN ADVANCE

 

[weaves]

Hey everyone - My 04 4.7L v8 is having misfire on all cylinders, codes P300-P308. When I start it up, it will run for a few seconds until it dies. I was able to eventually start it up enough to where it would idle until I turned the key off. The idle is really, really rough though. No response to throttle (kills it), but when it revs up to 2k on start, it sounds perfect, it just gets rough when it comes back down to ~500-1k RPMs.

So, this started happening when I replaced the starter. I installed new gaskets for the lower manifold (didn't remove upper) - originally didn't swap injector o-rings and grommets, but when I ripped it apart to do it again after having issues, I used all new rubber.

One thing that did happen after I could get it to run for a bit was tons of smoke coming from passenger side cat, which has an O2 sensor I replaced about a year ago that hasn't given me any problems. It seems to have all burnt off though because there is no more smoke.

I built a DIY smoke machine and tested for vacuum leaks from the intake duct after the MAF, didn't see any leaks but there is a chance I couldn't get enough smoke past the throttle body flange, i'll be testing that again.

I cleaned MAF and throttle body.

I replaced all spark plugs. Nothing too bad with the old ones other than one with a lot of oil on it (I have leaky valve cover gaskets, going to swap those this weekend too)

I have a fuel pressure gauge but I either 1. don't know what tf I'm doing or 2. it is faulty, because I'm getting 0 pressure from the inline, despite hearing the pump come on and getting some fuel delivery. I want to spend more time on this this weekend.

One thing that could be cause for concern, because I lubed up the injector o rings and grommets, I have injectors that are easy to rotate in their spots, but no leaky injectors. How tight are these fuel rails supposed to be? No torque spec in Chilton manual.

I have noticed that when I crack open a banjo bolt on the crossover, or when I swapped the fuel pressure regulator that, even though fuel comes out, it doesn't seem to be as pressurized as it could be, given the volume that comes out.

I replaced PVC and PVC hose.

I'm really leaning towards it being a fuel delivery problem, but what are the chances that I could have dead fuel parts right when I fix a starter?

THANKS IN ADVANCE

If it ran fine prior to replacing the starter, then chances are parts weren't installed correctly or something got damaged in the process. P0308 is a misfire for cylinder 8 which is the cylinder closest to the firewall on the P/S bank. I'd start there and then inspect the rest of your spark plugs. Make sure that the vacuum line leading to the fuel pressure regulator is on securely and free of cracks. Also, verify that you installed the intake manifold gaskets in the proper orientation - the white tab on the gaskets should be on the top and facing toward the intake manifold.

First thing to do is to throw the Chilton's manual in the garbage and download the Factory Service Manual below. You will want the 2003 manual for your 2004 MY.

The fuel injectors should move fairly easily back in forth on the fuel rails but you can easily damage the o-rings by rotating them. The torque spec for the fuel rail nuts are 16 ft/lbs. You should also replace the banjo crush washers anytime you remove a banjo bolt.

Service Manual Download Links.

 

[Elan750]

could you have mixed up a coil? or didnt properly seat it? Camshaft position sensor damaged or not plugged in?

 

[08TxRunner]

Honestly it sounds like a massive vacuum leak to me, maybe that lower manifold gasket. Get it idling and spray it down with brake cleaner. If it stumbles and dies when you hit a spot, you've found it.

 

[4thGen4.7]

could you have mixed up a coil? or didnt properly seat it? Camshaft position sensor damaged or not plugged in?

I don't think so - problems came up prior to messing with any coils. Camshaft position sensor hasn't been touched but I can certainly double check that. Thank you for your reply

 

[4thGen4.7]

Honestly it sounds like a massive vacuum leak to me, maybe that lower manifold gasket. Get it idling and spray it down with brake cleaner. If it stumbles and dies when you hit a spot, you've found it.

Considering I didn't actually look at orientation, just whether it fit over the holes and studs... this could be it. I'll take a look and report back.

 

[4thGen4.7]

If it ran fine prior to replacing the starter, then chances are parts weren't installed correctly or something got damaged in the process. P0308 is a misfire for cylinder 8 which is the cylinder closest to the firewall on the P/S bank. I'd start there and then inspect the rest of your spark plugs. Make sure that the vacuum line leading to the fuel pressure regulator is on securely and free of cracks. Also, verify that you installed the intake manifold gaskets in the proper orientation - the white tab on the gaskets should be on the top and facing toward the intake manifold.

First thing to do is to throw the Chilton's manual in the garbage and download the Factory Service Manual below. You will want the 2003 manual for your 2004 MY.

The fuel injectors should move fairly easily back in forth on the fuel rails but you can easily damage the o-rings by rotating them. The torque spec for the fuel rail nuts are 16 ft/lbs. You should also replace the banjo crush washers anytime you remove a banjo bolt.

Service Manual Download Links.

This is all great - thank you for your reply. Thanks for sharing the link to the big boy manual - I like the pictures in the Chilton though haha, this is much more informative though so I'll toes it. I'm actually thinking it is going to be the gasket.. I didn't actually check the orientation, other than just whether or not it fit over the studs and holes, like I mentioned to the other reply. Considering the fuel seems to be delivering fine. Spark is fine. It seems like it needs to be vacuum related. I'll report back asap.

 

[Trent]

I hate to be the one to ask, but did you check the gaps on the new plugs?

 

[AuSeeker]

I hate to be the one to ask, but did you check the gaps on the new plugs?

The iridium plugs for the V8 come pre-gapped and you can damage them if you try to adjust the gap, but it would be OK to at least check them...but I have seen many old iridium plugs that had close to twice the recommended gap and the vehicle ran rather well considering.

 

[4thGen4.7]

Update: I ripped it apart and replaced the FEL-PRO gasket I got from O'Reilly's (absolute POS) with a Beck Arnley that was much higher quality and looked closer to OEM. The FEL-PRO had a blow out and you could see where the manifold came off the edge a little bit. Needless to say, I was confident when putting the new gasket in. Unfortunately, this did not do the trick. I kept checking for vacuuum leaks, spark, fuel pressure, and could not find anything wrong. I had it towed to the dealer and their code reader is showing bad engine immobilizer chip. My cheap code reader did not pick that up. I told them to go ahead and replace it but I had serious doubts that was the issue ($370 to make sure that didn't shit the bed at some other point in my life I guess). Now that I am reading more about these chips, it appears that rough idle is a symptom because it can turn off fuel injection? I'm not so sure.

I will update once I hear back.

 

[4thGen4.7]

Update: I ripped it apart and replaced the FEL-PRO gasket I got from O'Reilly's (absolute POS) with a Beck Arnley that was much higher quality and looked closer to OEM. The FEL-PRO had a blow out and you could see where the manifold came off the edge a little bit. Needless to say, I was confident when putting the new gasket in. Unfortunately, this did not do the trick. I kept checking for vacuuum leaks, spark, fuel pressure, and could not find anything wrong. I had it towed to the dealer and their code reader is showing bad engine immobilizer chip. My cheap code reader did not pick that up. I told them to go ahead and replace it but I had serious doubts that was the issue ($370 to make sure that didn't shit the bed at some other point in my life I guess). Now that I am reading more about these chips, it appears that rough idle is a symptom because it can turn off fuel injection? I'm not so sure.

I will update once I hear back.

I want to preface this by saying, I only took it to the dealer because I was assured it could be looked at sooner than every other shop in town could guarantee. I knew I would be F'd but I could never imagine how badly.

This has been an absolute nightmare. I am surprised I do not have a stomach ulcer from the stress. The timeline looks like this:

11/12 - Dropped off the truck, told it will be $91 for the diag. I say ok. and brief the jabroni on everything that I did to it, including the current state: It runs, but needs to be warmed up - once it warms up, it idles but doesn't respond the throttle, and instead, dies.
11/13 - This is when I was promised it would be looked at - after calling repeatedly, I cannot get the service rep on the phone
11/14 - finally get a call back from the service rep, says it is a bad engine immobilizer. I ask if this could be causing my issues with a rough idle, he says yes. gut says hell no, but 'it must be fixed to proceed' - okay man.. go ahead. I call in the afternoon, service rep has left for the day.. nice.
11/15 - get a call first thing, service rep says.. I kid you not "Okay, we're now able to get it to start up but when the tech mashed the accelerator it dies" - :toilet: - dude.. that is where we started. What happened to it having a rough idle because of the immobilizer? He then goes on to say that the tech has now noticed arching from the starter wire... they must remove the manifold, get in and repair that, and put it back on. That will be $273.. plus $273 more "to continue the diagnosis". So, now I must feed the man more money to keep working.. such arbitrary BS. I told him to just go in and fix the arching. 2pm comes around - supposedly 2 corners of the manifold are broken and nuts are rounded... I was aware of 1 nut cross-threaded when taking it in but no way this other stuff had been done to it.
He says I have 3 options - bring in a manifold I source myself, reuse the old manifold, buy a new one from Toyota for $1500. I tell him to reuse the manifold. 1 hour goes by and he calls back to say the master tech won't allow it. I must replace it. So I managed to get to a scrap yard with just enough time to find a Sequoia and rip out the manifold took about 45mins and I was 1 minute away from being locked in the scrap yard.
I waltz into the dealership with the manifold like a f'ing trophy buck, hand it over to the rep and he looks me in the face and says 'thanks, i'll call you monday' (11/18). Mind you, they were open for 2 more hours, and all day on saturday. I'm brushed off when trying to clarify how that works. Apparently there are only 2 techs left for the next two days and I guess mine doesn't make them enough money. OK whatever.
11/18 - I call and am told that the parts (nuts and gaskets) should be in that afternoon. I call with 2 hours left to close. Parts aren't there. WTF
11/19 - I'm swamped at work so I call at the end of the day, dude has left for the day. Front desk lady is so sympathetic that she has to keep hearing from me that she finds another rep to help - not much inter-office comms because that dude had completely different info from everything i've been told.
11/20 - I call first thing in the a.m. parts are on backorder. apparently they are having a tough time getting the studs for the manifold. Tonight a slew of highly descriptive reviews have made the rounds on the internet - i've decided to pivot from being a customer not worth their time, to a customer that is now making every effort to cost them as much money as possible
11/21 - I get a call and the parts have conveniently arrived, almost an entire week since I was told the manifold needed replacing. 9 days since dropping it off. All that has been done to it is the replacement of an immobilizer that had nothing to do with the problem at hand, and had never been causing issues in the past and a torn apart manifold. My rep is very keen to let me know when he's leaving for the day and that he won't be in tomorrow. he's very optimistic about the work to be done.
11/22 - I get a call first thing from the head man - apparently my reviews have made the rounds. I'm given his personal number and the time to air all of my grievances. I'm a 1 car household and live 10 miles from my office. This has been a debilitating processes. He assures me he'll have a man on it at all times. End of day, he says he'll have to have his master tech on it when he gets back on Monday from a training.
11/25 - I give it until after lunch to call. My call is returned at 1:45. Master tech is scanning it and checking the numbers. He's saying it could be the ECM. I say no f'n way. Remind him that the 3 parts of combustion is fuel, spark, and air. I've heard fuel pressure is good but no word on the leak down test I suggested might be good to do or whether they're confident on spark.
I called again just now. No answer.

Thanks for reading

TLDR - If you think Toyota is gonna screw you, you're wrong, they're gonna
screw you so much harder.

 

[jmildoc]

How did you fix this!?!?!?!?