misfire at 2000-2300 RPM and limp mode

hello taco world...turning to you guys bc many of my trouble shooting ideas have come from you, so thanks and please help!

i have a '96 2.4l tacoma, 77k miles.

it has a constant misfire at about 2000-2300 RPM, either at idle or while running.

sometimes drives good, other times will run then go into a limp mode and check engine light comes on.

Does not throw a code my basic code reader can read, and turning truck off for a brief period of time the code goes away and then limp mode goes away.

Figured something with temperature, but changed what I know…asking for ideas before I shell out $$$ on a new computer…?

*side note, when I first had the issue, I took it to Toyota and they said it was the distributor and changed it out….no fix, so I called back and they said spark plugs and cables, so I changed. Still no fix, but when I called, they said b/c I worked on it that it voided their work and would have to charge me all over again.

Any thoughts…thanks again for the support.



New parts…

distributor...toyota
coolant Temperature Sensor...new
radiator cap...new
o2 sensors...new
positive Crankcase Ventilation (PCV) Valve...new
mass air flow sensor...new
spark plugs...new
spark plug cables...new
fuel pump...new
fuel filter...new
crankshaft Position Sensor...new
gas cap...new
fuel Injection Pressure Regulator...new
catalytic Converter...new
thermostat...new
air Intake / Charge Temperature Sensor...new
ambient Air Temperature Sensor...new
knock sensors...new
ignition Control Module (ICM)...new



Refurbished or used part tired…

EGR valve...used
throttle body...used
idle Air Control (IAC) Valve...used
throttle Position Sensor (TPS)...used
injectors...refurbished

 

Well gosh. Find a new mechanic. Do a compression check, post your findings. Have valve shim clearances been checked/adjusted? If not, do and post findings. And what code was it giving?

 

hi Jakuku,
i did take to another mechanic shop who "specialized" in japanese vehicles, and held it for 3 days and said they were stumped bc they could not figure out.
i did a compression test and all good.
it does not throw a code...or one my code reader can read, and clears by turning off/on.
i will need to look into the shim clearance, but has not been adjusted previously.
thanks for the info...

 

What was the compression? Did you test it wet and dry? A hanes manual or Timmy the toolman's videos will help you with the valve clearnance check. Just need a feeler gauge. Pop off the valve cover and measure the clearances. You have to rotate them so the cam is in the proper position for TDC for the valve you're measuring.

 

if i remember correctly it was around 160ish more give or take.
its been a while since done, but i just remeber all four chambers were with in 5psi of eachother.

 

You say it doesn't throw a code your reader can read. But does it throw a code it can't read? As in, is your check engine light on? Have you had it read by someone with a reader that can read it? If so, what was it?Many readers can't some can. Trial and error. Was the compression check done before this problem started? If so, it would warrant checking again. Anyhoo, the valve shim clearance check would be my next step.