Many codes and engine runs rough

p0100 maf or vaf A circuit malfunction
p0110 IAT sensor circuit malfunction
p1135 manufacturer control fuel air metering
p0300 random multiple cylinder misfire detected
p0301 cylinder 1 misfire
p0304 cylinder 4 misfire
p0305 cylinder 5 misfire
p0306 cylinder 6 misfire

These are the codes I just read from a 2001 Tacoma V6 2WD. Changed plugs and wires (not packs) last night and of cource this is when it started running worse than when I began. I used NGK dual tip plugs like the factory had put in it.

The CEL was on previously but I'm not sure what code it was. The truck has been going down hill since late August when I bought it with 134,000 miles on it.

The truck has not had regular maintenance ever, original everything! Oil change and tire related stuff would be my guess at the only work done to it. Original belts hoses and timing/water pump....everything.

When I pulled the plugs on the drivers side they looked different than the passenger side, darker and looks like oil deposits. I originally bought single tip NGK plugs so after I read that's a nono I then bought the dual tip NGK's. With the new plugs I ran it for maybe a half hour last night and when I swapped them for the dual tips today the same side was darker and seems to have oil deposits!

I'm not well versed working on automobiles and usually pay for all my service but times are harder now and I'm trying to save money. The local garage I go to wanted 2.6 hours and $210 just labor costs to change my plugs so I said no way.

Please help me!

V/r,

Ray H.

 

by all wiring, do you really mean all wiring under the hood that seems easily accessible? I wouldn't know what wires do what!

Any tips?

 

The coil packs are tight, drivers side plugs and popped into place and everything is the way I found it (to my eyes anyway!).

I did one plug at a time and when I replaced drivers side wires also one at a time.

I disconnected the battery before I began.

I'm at a total loss here......

 

Ran engine with radiator cap off and nothing shot out and it looked like it did with engine off.

Guess I need to hit the parts store for some carb cleaner and electrical contact cleaner. Any suggestions on what to buy from Oreilly's or Advanced Auto?

I'm going to assume there's not an easy or inexpensive way to check compression at home. I have sockets/wrenches and bought a code reader today so I don't think I have on hand what it might take to see if it's a head gasket/valve seals or bad compression/shot rings etc...

Regarding the performance of the truck;

When purchased it ran fine. Just the last month it started hesitating when accelerating and I have had trouble getting to 65MPH+ with my 17' Bayliner boat in tow (2100lbs tops). Now the real change started last night after I changed plugs/wires.

It has never run this rough but a week ago it died on the highway at a stop light and took a bit to start back up. Had to manipulate the accelerator and when it started gave a big backfire from somewhere. It has backfired a few times since then and a friend asked if it could be the catalytic converter being plugged/clogged. I do not smell rotten eggs but I do smell what I can only describe as a flooded gas smell from the engine and exhaust.

When it starts, albeit very rough as some cylinders are not firing, it will not rev up to anything. In fact it's not able to get past about 3.5-4K RPM's and it does take a few seconds to get there and it then starts dropping off. It just all around runs like crap and I'm not sure how to proceed but I know the bank account can't stand another hit!

 

Forgot to add that I found this in a search on how to clean the MAF;

http://4runners.org/writeups/throttle/index.html

Going to attempt this as soon as I get some cleaner.

 

sounds like a MAF sensor. check the junk yard for a quick 20 dollar replacement(if they sell it that cheap) and try it out. some misfires can be caused by MAF sensor issues.

 

Cleaned TB and MAF. TB with gumout carb cleaner, toothbrush and cloth as the guide says and the same for th MAF. Took it out and sprayed it down, let it dry and did it again.

Truck still has the same issues but less codes this time!

P1135
P0300
P0304
P0306


Thoughts before all the auto parts stores close for the day?

Thanks everyone for all the support!
Ray H.

 

CEL obviously still lit but when RPM's go up it flashes.

Also, since I cleaned the TB and MAF acceleration seems a bit more responsive but it still shakes the truck when idling and just sounds plain wrong. Once RPM's get up past 3K it can now go higher than before! Guess that's a good sign anyway.

 

I used the code scanner to erase and I saw the CEL off just for a brief moment. Is removing the battery power more effective or better than erasing with code scanner?

It's idling now in the yard but I'm sure not going to drive it anywhere, nobody to tow me home if I get stranded!

So now to the misfiring, which one is 4 and which one is 6? If the plugs are new and at least one plug wire is new how do I determine what is causing the misfire? I've read checking resistance with Ohm meter but I lack one but do have a volt meter

Since the P1135 is there everytime I'm guessing it was the one that was lit when I bought it. However, 304 and 306 were not and it has never run this way, any ideas?

 

I left it idling after I cleaned TB and MAF and reset codes. Right away I got the P1135 and 304/306. Came inside for a cold one (November and it's 77F outside in direct sun!) went back out to see if anymore codes appeared and we can add 305 to the list.

What's going on here?! Am I going to need to sell a kidney to get a mechanic to fix this or can I get this done at home?