1999 Prerunner 3.4 Won’t Start

Bman12

Member
Hello all,

During a head gasket replacement, I ended up having to remove the exhaust cam on the driver side to remove a piece of debris that was under it. I replaced the cam in what I thought was the same position but when I got everything buttoned up it wouldn’t start. Cranked and fired but was really rough and shook a lot but wouldn’t start. Figuring I must have put the cam back wrong, I reopened it all up, realigned the cam to ensure the driver side had the single dots lined up and the double dots to the outside. Buttoned it all up again, and still doing the same and not starting. No codes. I am not sure what it could be. Any ideas? Is my timing still off? The only cam I took out was the driver side exhaust so as long as I lined up the single dots, it everything else should be timed correct, right? Any help is appreciated!
 
He's on just about every other thread here, and probably still on tw. I think he has claimed to have just about every issue you can think of on these gen1's. Very surprise he hasn't chimed in yet. I know by now he's read this.
At any rate without watching exactly what you did. it could very well be a timing issue from what you now claim how the engine is running.
 
He's on just about every other thread here, and probably still on tw. I think he has claimed to have just about every issue you can think of on these gen1's. Very surprise he hasn't chimed in yet. I know by now he's read this.
At any rate without watching exactly what you did. it could very well be a timing issue from what you now claim how the engine is running.
I’m wondering if it’s electrical. I pulled the timing cover off and the cam wheels are both at 12:00 when the crank is at 0 and I lined up the single dots on the cam I took out so that should be good too.
 
Just for ha ha's, have you checked for any codes?

Come-on jay, could use your help...this is in your wheelhouse...another gen1 with a 3.4
 
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How was it running prior to the head gasket replacement? Could have you had this issue before with it? I asked a friend of mine thats an auto tech.... he's serviced several of these 3.4 v6's...he had no answer as it's pretty much straight forward replacing head gaskets. Only thing he could think of it may be 5 finger drift. On these older trucks, anything is possible as they accumulate more mileage. I wish I could be of more help, but never had to tear down a toyota engine in, or out of warranty. You develop a sixth sense when it's time to send them down the road. Only experience is with a number of older gm push rod v8's, and their super simple vs these tacos.
 
How was it running prior to the head gasket replacement? Could have you had this issue before with it? I asked a friend of mine thats an auto tech.... he's serviced several of these 3.4 v6's...he had no answer as it's pretty much straight forward replacing head gaskets. Only thing he could think of it may be 5 finger drift. On these older trucks, anything is possible as they accumulate more mileage. I wish I could be of more help, but never had to tear down a toyota engine in, or out of warranty. You develop a sixth sense when it's time to send them down the road. Only experience is with a number of older gm push rod v8's, and their super simple vs these tacos.
It was running perfect before. My only other thought is something off in the wiring harness after moving it around to get the covers off. 25 year old wires getting yanked around. The other thing is a previous owner had put some sort of keyless security device on it. I’ve had issues where if the battery died I’d have to press a button on this device to reset the ignition, otherwise you’d just turn the key no nothing would happen as far as the starter moving. Maybe something with that system is messing with the ignition. I don’t know. I appreciate the help though.
 
Idk, toyota wiring harness's, and associated electrical's have always been better than average vs other brands. Could have you damage a plug connector somewhere during this repair? You'd think a code would be present if the case.
 
Gotta ask jay here, he's our resident 3.4 expert on these gen1's.

i have yet to encounter any such issue as this
it would just be guessing on my part at stuff i have no clue about the workings of
until i get more educated
 
Come on jay, you're being way too modest. You've been telling all of us here how you have replaced just about everything, but the windshield washer reservoir cap in that 97 of yours. Surely just by going back to all the issues you've had, you must have some idea?
Stopped by a buddies auto shop on the way to the grocery mart this morning just before they started, and asked if they had any idea what an issue as such could be. He thinks the timing could now be off a tooth somewhere between either of the cams in relation to the crank pulley tdc mark.
 
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no encounters yet with head gasket or timing issues

are you using the FSM for directives?
 
Unfortunately there's a bit more to it with these later engines we have now. I remember rebuilding, or freshening up my 389, and 421 gm engines back in the day right in a garage I rented. If any machine work was needed we had several shops in our area that would have it ready by later in the day. Never missed a weekend at the drags the entire summer.
 
Come on jay, you're being way too modest. You've been telling all of us here how you have replaced just about everything, but the windshield washer reservoir cap in that 97 of yours. Surely just by going back to all the issues you've had, you must have some idea?
Stopped by a buddies auto shop on the way to the grocery mart this morning just before they started, and asked if they had any idea what an issue as such could be. He thinks the timing could now be off a tooth somewhere between either of the cams in relation to the crank pulley tdc mark.
Hmm off by a tooth? I would think it would at least start but run a little advanced or retarded…
 
Was told it's a common mistake when installing the two cams in the head that its easy to get them misaligned with each other that causes the timing to be off. Not claiming thats what it is, but I'd double check it.
 
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