If there is someone on here that has access to TIS and can give me the troubleshooting steps for a random miss-fire on a 2001 Tundra 4.7 (cyl 3-5-7)
Back story:
I bought a used Tundra for hauling my trailer, after about a week it developed a very bad stumble and it would come and go. It was throwing a random misfire code and in my data stream (Genysis EVO Scan tool) it showed the misfires were on 3-5-7.
I notice that half the coli packs on the thing were non-branded and the few Denso ones that were left had paint marks all over them (I am assuming from someone before me chasing the same problem)
I called the dealer for coil packs but they were asking $208 each for them and none were in stock. So a quick trip to advanced netted me 8 coil packs for under $400, while I was at it, I bought 8 new Denso plugs (platinum) fuel filter, Air filter, MAF cleaner, TB Cleaner and some carb cleaner (to check for vacuum leaks).
I replaced all 8 coil packs, all the plugs, filters, cleaned the MAF, and TB and lastly check for vacuum leaks (found one and fixed it with some new vacuum line)
Well I had the same problem, ran fine for two days and then fell on its face hard. If I kept the RPMs above 2500 it would smooth out.
So Now I needed to check the compression, fuel pressure, and injector signal, something I did not have the time or tools for.
So I took it to the dealer just down the road and asked them to find the problem, and what I had tried so far.
So I asked them to check the fuel pressure, compression, and voltage to the injectors, also asked them to check the timing belt (tundra forums had mention of bad tensioner causing the belt to jump a tooth)
Over the last 6 weeks YES 6 WEEKS, they have called me about as many times.
The first call was the writer telling me that the coil packs were aftermarket, and would have to be replaced with OEM coils before they could test it. I asked them why they could not OHM the coils out and see if they were bad.... he said he would get back to me.
Next he calls and says the tech said it was the injectors, I questioned why he thought it would be 3-4 injectors at once going bad and asked if he had checked fuel pressure and compression. He said they had checked both and both were good. After much hesitation I told them they could do one injector in one of the trouble cylinders and see if it fixes that cylinder (injectors $188).
Third call, he tells me that the injector did not fix the misfire, and insists on new coil packs. I rant for a moment about their ability to swap parts without any real trouble shooting, and again tell him no, on the coil packs. I ask him to check into the timing because it was one of my original concerns.
4th call, he tells me that the timing had jumped two teeth, so the tech put it back together correctly and it did not fix the problem....?????? let that sink in for a moment... (Worth mentioning; the timing belt was just done less than 10k ago at another local dealer.) He tells me that the tensioner and belt were both NON Toyota, and that could have been why it jumped. So I asked “what now” if that did not fix it, and why did he not call me to have me replace the non OEM when he had it apart. He said the tech was just trying to get it figured out and he put it back together.
Fifth call, they writer tells me, it needs a new engine, and he was pretty sure I did not want to spend that kind of money. I asked “what was the reason for the new diagnosis”, to which he replied “the tech said the jumped belt probably bent some valves”. So I pointed out that it ran fine from time to time, and the tech said the compression was good. He said he will call me back.
6th call, he says the tech only tested on cylinder for compression before, but now he went ahead and check all 8 and compression was good so it probably did not need a motor. He went on to tell me the “master tech” and “his very best mechanic” insists it is the injectors still. So I ask, how much do I owe you right now? $1200 he says, 1200 dollars for no real troubleshooting and absolutely no resolution. He informs me that the tech cannot possibly do any more unless he replaces the non OEM parts with OEM parts. So after some very long ranting and venting, I tell him to do it, replace the coils, injectors, fuel filter, timing tensioner, and spark plugs (because he said that is not the part number in their computer for the standard plugs)
Yesterday, he calls me to let me know I could come pick the truck up, it was done…. I said “great, did it fix it?” and to my disbelief he said “it’s a little better but it still has a couple random misfires”… So I say, once again the tech had no idea and just wanted to replace parts, and I asked how much I owe him for all the hard work they have done…sit down….$3400. After I started breathing again, I asked him what exactly I should do with a truck that they cannot make run, but want half the price for the truck for “repairs”. So he has the intestinal fortitude to tell me, the tech said it needs a new computer and perhaps a wiring harness. WHY, I said, to which he replies, the computer in it looks damaged and so does the harness. But he assures me, there is no way the tech could have known to check the ECM prior to this point and investment. I remind him of a conversation we had about checking for a re-flash in case the issue was in the computer, and he says, well there was no re-flash avail, so we just passed over that. He also offered to replace the ECM for $900 pus labor, and it may help the problem, but it may need the harness also.
So what I want to know, for sure, is there a point where (if he were troubleshooting properly) he would have checked the ECM and noticed the “damage”? Something made him check the ECM after he replaced everything else and wanted to replace the motor. So should he have looked at the ECM or tested voltage there during troubleshooting? I need to know and have proof before I go to pick this thing up, so any help with this would be AWESOME. Preferable, a copy of something that shows what steps to take and what to test for above described problems.
:frusty:
Back story:
I bought a used Tundra for hauling my trailer, after about a week it developed a very bad stumble and it would come and go. It was throwing a random misfire code and in my data stream (Genysis EVO Scan tool) it showed the misfires were on 3-5-7.
I notice that half the coli packs on the thing were non-branded and the few Denso ones that were left had paint marks all over them (I am assuming from someone before me chasing the same problem)
I called the dealer for coil packs but they were asking $208 each for them and none were in stock. So a quick trip to advanced netted me 8 coil packs for under $400, while I was at it, I bought 8 new Denso plugs (platinum) fuel filter, Air filter, MAF cleaner, TB Cleaner and some carb cleaner (to check for vacuum leaks).
I replaced all 8 coil packs, all the plugs, filters, cleaned the MAF, and TB and lastly check for vacuum leaks (found one and fixed it with some new vacuum line)
Well I had the same problem, ran fine for two days and then fell on its face hard. If I kept the RPMs above 2500 it would smooth out.
So Now I needed to check the compression, fuel pressure, and injector signal, something I did not have the time or tools for.
So I took it to the dealer just down the road and asked them to find the problem, and what I had tried so far.
So I asked them to check the fuel pressure, compression, and voltage to the injectors, also asked them to check the timing belt (tundra forums had mention of bad tensioner causing the belt to jump a tooth)
Over the last 6 weeks YES 6 WEEKS, they have called me about as many times.
The first call was the writer telling me that the coil packs were aftermarket, and would have to be replaced with OEM coils before they could test it. I asked them why they could not OHM the coils out and see if they were bad.... he said he would get back to me.
Next he calls and says the tech said it was the injectors, I questioned why he thought it would be 3-4 injectors at once going bad and asked if he had checked fuel pressure and compression. He said they had checked both and both were good. After much hesitation I told them they could do one injector in one of the trouble cylinders and see if it fixes that cylinder (injectors $188).
Third call, he tells me that the injector did not fix the misfire, and insists on new coil packs. I rant for a moment about their ability to swap parts without any real trouble shooting, and again tell him no, on the coil packs. I ask him to check into the timing because it was one of my original concerns.
4th call, he tells me that the timing had jumped two teeth, so the tech put it back together correctly and it did not fix the problem....?????? let that sink in for a moment... (Worth mentioning; the timing belt was just done less than 10k ago at another local dealer.) He tells me that the tensioner and belt were both NON Toyota, and that could have been why it jumped. So I asked “what now” if that did not fix it, and why did he not call me to have me replace the non OEM when he had it apart. He said the tech was just trying to get it figured out and he put it back together.
Fifth call, they writer tells me, it needs a new engine, and he was pretty sure I did not want to spend that kind of money. I asked “what was the reason for the new diagnosis”, to which he replied “the tech said the jumped belt probably bent some valves”. So I pointed out that it ran fine from time to time, and the tech said the compression was good. He said he will call me back.
6th call, he says the tech only tested on cylinder for compression before, but now he went ahead and check all 8 and compression was good so it probably did not need a motor. He went on to tell me the “master tech” and “his very best mechanic” insists it is the injectors still. So I ask, how much do I owe you right now? $1200 he says, 1200 dollars for no real troubleshooting and absolutely no resolution. He informs me that the tech cannot possibly do any more unless he replaces the non OEM parts with OEM parts. So after some very long ranting and venting, I tell him to do it, replace the coils, injectors, fuel filter, timing tensioner, and spark plugs (because he said that is not the part number in their computer for the standard plugs)
Yesterday, he calls me to let me know I could come pick the truck up, it was done…. I said “great, did it fix it?” and to my disbelief he said “it’s a little better but it still has a couple random misfires”… So I say, once again the tech had no idea and just wanted to replace parts, and I asked how much I owe him for all the hard work they have done…sit down….$3400. After I started breathing again, I asked him what exactly I should do with a truck that they cannot make run, but want half the price for the truck for “repairs”. So he has the intestinal fortitude to tell me, the tech said it needs a new computer and perhaps a wiring harness. WHY, I said, to which he replies, the computer in it looks damaged and so does the harness. But he assures me, there is no way the tech could have known to check the ECM prior to this point and investment. I remind him of a conversation we had about checking for a re-flash in case the issue was in the computer, and he says, well there was no re-flash avail, so we just passed over that. He also offered to replace the ECM for $900 pus labor, and it may help the problem, but it may need the harness also.
THE END
So what I want to know, for sure, is there a point where (if he were troubleshooting properly) he would have checked the ECM and noticed the “damage”? Something made him check the ECM after he replaced everything else and wanted to replace the motor. So should he have looked at the ECM or tested voltage there during troubleshooting? I need to know and have proof before I go to pick this thing up, so any help with this would be AWESOME. Preferable, a copy of something that shows what steps to take and what to test for above described problems.
:frusty:
