2.7 3rz issue

Hey guys new to the forum. Ive been chasing an issue with my 2000 2.7 5spd tacoma. Started misfiring every time it cranked up after it sat longer than at least 6hrs. The misfire only lasted a few seconds then went away and ran absolutely fine. Then 3 weeks ago it started a slight misfire/rough and low idle when engine was at operating temp. Started with spark plugs. Since both my coil packs and plug wires were only a year old. And no change. Replaced o2 sensor (no catalytic converter) then inspected my injectors. Tested them and cleaned them and they were in rough shape to say the least. Replaced with new TRQ brand. In the process While i had intake off I noticed how dirty the throttle body was. Sprayed a small amount of seafoam down the throat and put everything back together. Now the truck hesitates to start will not stay running misfiring all over the place and smoking. If you Spray a little carb cleaner in the intake it revs just fine. Thought it was faulty injectors so i tested them and they all seem to be fine. put old ones back in just to confirm my suspicion and same thing.. replaced coils and plug wires again no change. Cannot find a vacuum leak anywhere. Has a new fuel filter and pcv valve. Pulled throttle body off and the backside is covered in carbon. Pulled whole intake manifold off and its also pretty bad. Egr plunger seems to work fine but its dirty as well. Right now im in the process of cleaning all of this. Is it possible the seafoam may have broke some of that trash up in the throttle body and messed my tps or iac up to cause it to do this? Just really dont know how its supposed to react when either one of those are faulty since I haven’t dealt with efi systems in depth very much. Was gonna by a new iac and tps but the prices on oem is crazy! Just didnt want to waste the money if i didnt have too. Or if im going in the wrong direction here. Any help or input is very much appreciated! Sorry for the long message. This is my daily and need it back on the road asap. My back up is a 86 squarebody with no a/c in this South Georgia heat lol

 

Yes, probably gunked up IAC further. Carb cleaner isn’t good to use on the throttle body either. Some info here on IAC cleaning if you will search a bit.

 

I hope so i just ordered one today, and i had read to only use throttle body cleaner so i kept that in mind. I was only spraying carb cleaner through inlet on the intake from vacuum line off the brake booster just to keep it running. But thank you

 

If IAC is stuck closed then the truck won’t idle worth a crap. Does it run ok if you open the throttle a little? Been there done that. Cleaned my old IAC and it still had issue, weak solenoid I guess and maybe from cleaner. Put an aftermarket IAC in which worked ok but had high idle, like 900 at normal op temp. It let more air in than OEM IAC. Put new OEM IAC and it works like it should, 700 rpm at normal op temp. And if you gonna. Lean the intake then don’t neglect the EGR port going into the plenum. It’ll carbon shut and can cause heat and head gasket failure, per OldSilver whom I trust.

No idea on why you are seeing smoke.

 

No it doesn’t get any better with throttle open, chokes down and stumbles and backfires through the intake. Will not even try to clear up or idle at least on all cylinders. But will run great on carb cleaner. This all started about 2 months prior when i washed under engine bay. Then the morning misfires started and gradually got worse over time. And once i sprayed in throttle body with seafoam during injector change thats when things went haywire.

 

Did you get the ole nag going again? What ended up being the issue?

I'm having the same symptom of misfires after sitting and am suspicious of leaky fuel injectors, per the raw fuel smell coming outta the exhaust.

I had my own thread going and the more tenured fellas convinced me to live with it, but reading this and the fact that we have the same truck is driving me to keep going.