aha2988
New member
So I went to a mud bog competition with my 03 V8 limited 4wd 4runner. couldnt stand sittin in the crowd so I cowboy'd up and got in line for the competition against many other trucks mostly running 40" tires or bigger. Long story short my OME lifted 33" tire running V8 won the competition 1st places coolest thing.
Drove home over heated a little due to mud packed in the radiator. no problems there just hosed out the radiator. Throughout the weekend I flushed an filled the coolant system, changed the oil, rotated the tires, and pressure washed the entire vehicle engine bay and all.
Monday morning got up to go to work and noticed a rough start/idle. started driving to work and my check engine light began to flash then eventually became permenant. The codes read p0300,p0301,p0303,p0305,p0307. p0351 p0357. The hole right bank of my motor wasn't firing properly.
After doing research and hunting down the problem I found alot of people are having an issue with a rough idle or missfire. even after changing coil packs, plugs, injectors, going into the gas tank to service fuel filters, the works.
What I found out through all my digging is that there is a rubber grommet that allows the cam positioning sensor wire to pass through the timing belt cover. This rubber gromets hole is about 2" in diameter plently big for mud rocks dirt water anything to get into your timing belt housing. In my troubles mud and rocks and dirt had made there way into the housing over the past three years of off roading, finally one of those pieces of trash fell in the right spot causing my timing belt to jump allowing my cam timing pully to move about 15 degrees off.
When dealships, in my case Toyota of Concords service shop change timing belts It seems its "less Trouble" for the techs to put this rubber gromet back in. To them it Seems to be a waste of time. But After researching and not really finding anything relating this problem to timing i wanted to share what I've found.
Now what i know is the 4.7 v8 engine of toyota's is from what i understand the only interference engine toyota makes SO WHY WOULD A TOYOTA TECH NOT PUT A SIMPLE GROMET IN PLACE TO PREVENT TOTAL ENGINE FAILURE IF THAT BELT WAS BE TO CUT OR TORN BY A PIECE OF TRASH!!!
So if your having firing issues or you have a V8 and have had your timing belt replaced check to make sure the rubber gromet to the cam position sensor wire is in place its located on the top right cam timing pully cover just under the top radiator hose. you'll see a grey wire connector follow that wire if there is a gapping hole where it goes into the housing its in your best intrest to seal that hole!!
Other solutions to the rough idle and misfiring can be as simple as a bad coil pack or clogged fuel injector. You can sometimes even get water down under your coil packs which will cause the spark plug to short out when attempting to fire. to test a coil pack pull it out, pull that cylinders spark plug out, plug the coil pack into the wiring harness that controls it, plug the spark plug into the coil pack, allow the ignition tip of the spark plug to touch a ground on the truck (away from the gas filled cylinder you pulled the spark plug out of!) if you see a little flame in the spark plug when engine cranks you know your coil pack is good. vacumm leaks can cause this issue aswell but are somewhat rare but to check just inspeck all vacumm hoses. If you have multiple misfires its probably a timing, or fuel dilivery issue. My part store sells these coil packs for like 81 bucks so don't just go replacing them if your unsure. I've found them at amazon for 35 for one 195 for a pack of 8.
I hope this helps some people out that may run into this issue. I'm trying to find out if The timing belt housing was designed to vent or if indeed its ment to be sealed. I would like to seal mine for future off roading atleast if it has to vented i can run a breather hose up and way from it. If anyone has info regaurding this please advise.
p.s. The same dealship that didnt put the gromet back in for me, wants to charge me $1800 to replace the tensioner pully/ bearings, timing belt, crank shaft seal, cam shaft seals, water pump, thermostate, coolant Everything that was destroyed thanks to there stupidity. I believe amazon has a kit for this for about $250 and i get to spend a day away from the wife and in the shop workin on my truck take that stealership basta@#%$@!!!
Drove home over heated a little due to mud packed in the radiator. no problems there just hosed out the radiator. Throughout the weekend I flushed an filled the coolant system, changed the oil, rotated the tires, and pressure washed the entire vehicle engine bay and all.
Monday morning got up to go to work and noticed a rough start/idle. started driving to work and my check engine light began to flash then eventually became permenant. The codes read p0300,p0301,p0303,p0305,p0307. p0351 p0357. The hole right bank of my motor wasn't firing properly.
After doing research and hunting down the problem I found alot of people are having an issue with a rough idle or missfire. even after changing coil packs, plugs, injectors, going into the gas tank to service fuel filters, the works.
What I found out through all my digging is that there is a rubber grommet that allows the cam positioning sensor wire to pass through the timing belt cover. This rubber gromets hole is about 2" in diameter plently big for mud rocks dirt water anything to get into your timing belt housing. In my troubles mud and rocks and dirt had made there way into the housing over the past three years of off roading, finally one of those pieces of trash fell in the right spot causing my timing belt to jump allowing my cam timing pully to move about 15 degrees off.
When dealships, in my case Toyota of Concords service shop change timing belts It seems its "less Trouble" for the techs to put this rubber gromet back in. To them it Seems to be a waste of time. But After researching and not really finding anything relating this problem to timing i wanted to share what I've found.
Now what i know is the 4.7 v8 engine of toyota's is from what i understand the only interference engine toyota makes SO WHY WOULD A TOYOTA TECH NOT PUT A SIMPLE GROMET IN PLACE TO PREVENT TOTAL ENGINE FAILURE IF THAT BELT WAS BE TO CUT OR TORN BY A PIECE OF TRASH!!!
So if your having firing issues or you have a V8 and have had your timing belt replaced check to make sure the rubber gromet to the cam position sensor wire is in place its located on the top right cam timing pully cover just under the top radiator hose. you'll see a grey wire connector follow that wire if there is a gapping hole where it goes into the housing its in your best intrest to seal that hole!!
Other solutions to the rough idle and misfiring can be as simple as a bad coil pack or clogged fuel injector. You can sometimes even get water down under your coil packs which will cause the spark plug to short out when attempting to fire. to test a coil pack pull it out, pull that cylinders spark plug out, plug the coil pack into the wiring harness that controls it, plug the spark plug into the coil pack, allow the ignition tip of the spark plug to touch a ground on the truck (away from the gas filled cylinder you pulled the spark plug out of!) if you see a little flame in the spark plug when engine cranks you know your coil pack is good. vacumm leaks can cause this issue aswell but are somewhat rare but to check just inspeck all vacumm hoses. If you have multiple misfires its probably a timing, or fuel dilivery issue. My part store sells these coil packs for like 81 bucks so don't just go replacing them if your unsure. I've found them at amazon for 35 for one 195 for a pack of 8.
I hope this helps some people out that may run into this issue. I'm trying to find out if The timing belt housing was designed to vent or if indeed its ment to be sealed. I would like to seal mine for future off roading atleast if it has to vented i can run a breather hose up and way from it. If anyone has info regaurding this please advise.
p.s. The same dealship that didnt put the gromet back in for me, wants to charge me $1800 to replace the tensioner pully/ bearings, timing belt, crank shaft seal, cam shaft seals, water pump, thermostate, coolant Everything that was destroyed thanks to there stupidity. I believe amazon has a kit for this for about $250 and i get to spend a day away from the wife and in the shop workin on my truck take that stealership basta@#%$@!!!
