Stalls at Startup

[donkeyhoatie]

Hi all,

I've got a 1998 SR5 with about 80K miles on it. My fuel efficiency had dropped a little bit, so I thought I'd change out the plugs and see if that helped at all.

I followed the tutorial in the FAQ area and changed out the 3 plugs on the passenger's side first. After putting the coils back on and putting the all the air stuff back in place, but before starting on the driver's side, I thought I'd start it up and make sure I didn't screw anything up.

Car started right up, but then stalled entirely. No matter what, I can't get it to keep running for more than about 5 seconds. I'm not quite sure what the issue would be. I've reconnected all hoses, but it seems almost like there's not enough fuel getting to the engine to keep it running. Or, it could be an air intake issue, I'm not sure.

I've never had this issue before after changing plugs (but to be honest, it had been a looooooong time since I'd ever had to replace them on anything). I feel like I probably just made one stupid mistake.

Sorry, no pictures of anything right now as the car is at my in-laws a couple of miles away and they don't have internet.

Any suggestion on what it might be? I'd like to get it taken care of right away, since it's my daily driver, but I can do without it for a couple of days if need be.

Thanks in advance. You guys are great here on the board.

 

[badattitude]

perhaps a vacume hose got knocked off. Check around the back of the throttle body.

 

[4-Ripcord]

Most likely a vacuum hose. Or you could have ruined the wires..

Did you ever end up swapping the other 3 plugs?..

 

[donkeyhoatie]

Most likely a vacuum hose. Or you could have ruined the wires..

Did you ever end up swapping the other 3 plugs?..

Any thoughts on what I could have done to ruin the wires?

Oh, and I haven't changed the other 3 plugs yet. I wanted to make sure I could get the stalling issue fixed before moving on to the other 3.

 

[GX4SEVEND]

Are the coil packs all sealed and making good contact? spark plugs torqued down correctly? Did you connect the other 3 to the coil packs?

 

[donkeyhoatie]

Are the coil packs all sealed and making good contact? spark plugs torqued down correctly? Did you connect the other 3 to the coil packs?

The coil packs seemed to be sealed well. I put a little grease around the edges. I thought they were making good contact with the plugs, but is there a good way to tell?

As for the torque on these, I didn't have a torque wrench available. The tutorial mentioned that you should hand-tighten until you get resistance, then give it another 1/4 turn. So, that's what I did. Would over- or under-tightening the plugs cause this to happen.

I don't think the plugs themselves are the issue, especially since it fires right up and sounds good. I'm more inclined to think there's something going on with the throttle, I'm just not sure what it could be, and everything was going fine before I started switching out the plugs.

 

[awpsome]

Most likely vacuum hose. Look around the bay for anything not plugged in to something.

 

[SP Jon M3]

Did you by chance unplug the MAF sensor while removing the air box assy and forget to plug it back in?

On the fuel efficiency, try cleaning the MAF and the idle control valve (a sticky ICV can also lead to the engine stalling). These were always getting gummed up on my 1st gen Tacoma. I made a habit of cleaning both of those every 30-40k miles.

 

[donkeyhoatie]

Thanks for the comments, all. I'll be swinging by the garage after work today to check the vacuum hoses and the MAF. Hoping it's just something dumb I forgot to put back in place, but keeping my fingers crossed that I didn't inadvertantly break the MAF, especially knowing how fragile they are.

 

[donkeyhoatie]

Finally got it figured out. After disassembling and re-assembling all the parts for changing out the plugs on the passenger side, I was able to determine it was definitely NOT something I forgot to put back/reattach.

So, I started poking around at the wiring, so see if something was un hitched anywhere. Lo and behold, the red (power, I think) wire for the ignition (I think) was broken on the harness right next to MAF. Whoever owned the car before I did cut it for some reason, maybe for a remote starter, and then crimped the two ends back together. Unfortunately, he did a really crappy job all around and the wires were pretty rotted out at both ends. While I was removing the wiring from the air hose, I must have jostled it loose and the wires came apart. I cut off the corroded section, stripped them down, twisted them together, and taped the whole thing up. The car still wouldn't start, but guessing from the strong smell of gas, I figured that I'd flooded the engine during the times I kept trying to get it to start.

The next day, after the gas had evaporated, I was able to fire it right up. Took it in to a local mechanic and had them run a new power line for me since I didn't have much to work with when I was reattaching them, I figured I'd feel safer having it done correctly. Plus, while they were at it, they put in the new plugs on the driver's side that I hadn't gotten to yet.

All in all, it set me back $100, but it was nice to know I wasn't a complete moron under the hood. I hadn't changed my plugs since I owned a 1979 Chevy Mallibu Classic back in the late 80's/early 90's, but even after that long of a break, I thought I should still be able to do it correctly. Nevertheless, it was fun getting back under the hood and poking around.

Next up, replacing my busted sway bar end links. I've sprayed them with penetrating lube a bunch of times, but it hasn't done much. I think I'll just soak some rags and let them sit on the bolts over night.

Thanks for everybody's help. This board is a treasure trove of knowledge.