SPONSORED LINKS

1987 Toyota 4Runner engine runs bad

Tiny
EDDIE440
  • MEMBER
  • 1987 TOYOTA 4RUNNER
Engine Performance problem
1987 Toyota 4Runner 4 cyl Four Wheel Drive Manual 0

its had a new engine put in. The guy I got it from was running it with a carb. I took it off and put it back fuel injected like it came from the factory. Now it dont want to start and when it does it runs like junk. It will not idle and the only way you can start it is to prop onpen the mass air flow so the fuel pump runs. When running it run rough and skips. I have replace almost everything on it electrical and check everything else to make sure it tested right. Really frustrated and almost ready to put the carb back on.
SPONSORED LINKS
Tuesday, September 23rd, 2008 AT 2:06 PM

13 Replies

Tiny
RASMATAZ
  • MECHANIC
  • 75,992 POSTS
Test the MAF what it does is ground the circuit opening relay in order for the fuel pump to fire up.

Clean out the idle air control valve and check the throttle position sensor closed and WOT voltages and also the O2 sensor
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Tuesday, September 23rd, 2008 AT 2:25 PM
Tiny
EDDIE440
  • MEMBER
  • 8 POSTS
Change the mass airflow sensor, completely cleaned the throttle body replaced tps, replaced fuel pump.
Was this
answer
helpful?
Yes
No
Tuesday, September 23rd, 2008 AT 2:33 PM
Tiny
RASMATAZ
  • MECHANIC
  • 75,992 POSTS
The fuel pump is it the original when the carb is being use-There's a different in pressure between the 2.

Check fuel pressure and have you tried adjusting the air screw
Was this
answer
helpful?
Yes
No
Tuesday, September 23rd, 2008 AT 2:38 PM
Tiny
EDDIE440
  • MEMBER
  • 8 POSTS
Changed pumps, air screw doesnt help
Was this
answer
helpful?
Yes
No
Tuesday, September 23rd, 2008 AT 2:56 PM
Tiny
RASMATAZ
  • MECHANIC
  • 75,992 POSTS
Ignition components are they in good condition? Did you clean out the IACV? Ignition timing is it okay? Check the fuel pressure and exhaust system for restriction.

BTW I need the fuel pressure readings in order to get to other areas w/o this info I'm stuck
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Tuesday, September 23rd, 2008 AT 3:18 PM
Tiny
EDDIE440
  • MEMBER
  • 8 POSTS
Tried those, good fuel pressure
Was this
answer
helpful?
Yes
No
Tuesday, September 23rd, 2008 AT 3:23 PM
Tiny
EDDIE440
  • MEMBER
  • 8 POSTS
Unhooked the exhaust at the converter, thought that might be it, no change
Was this
answer
helpful?
Yes
No
Tuesday, September 23rd, 2008 AT 3:25 PM
Tiny
RASMATAZ
  • MECHANIC
  • 75,992 POSTS
I need the actual pressure reading with and w/o the pressure regulator
Was this
answer
helpful?
Yes
No
Tuesday, September 23rd, 2008 AT 3:26 PM
Tiny
EDDIE440
  • MEMBER
  • 8 POSTS
Fuel pressure is at 36# book says must be between 33 to 38
Was this
answer
helpful?
Yes
No
Tuesday, September 23rd, 2008 AT 3:27 PM
Tiny
EDDIE440
  • MEMBER
  • 8 POSTS
Draining the fuel tank and replacing with fresh now. Maybe thats it. Just guessing have tried all other things that I can think of. By all the readings I get it should run perfect but it will not
Was this
answer
helpful?
Yes
No
+1
Tuesday, September 23rd, 2008 AT 3:31 PM
Tiny
RASMATAZ
  • MECHANIC
  • 75,992 POSTS
Have you checked for vacuum leaks and the vac hoses are routed propery to where its suppose to be.

Pull the vac hose from the regulator and check if it has gas in it or the reg
Was this
answer
helpful?
Yes
No
Tuesday, September 23rd, 2008 AT 3:34 PM
Tiny
RASMATAZ
  • MECHANIC
  • 75,992 POSTS
Since you have a repair manual check the injectors solenoid resistances
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Tuesday, September 23rd, 2008 AT 3:39 PM
Tiny
EDDIE440
  • MEMBER
  • 8 POSTS
Thanks for the help but I think I will take the engine apart and check it. I have come to the conclusion that its internal, new engine or not its has to be internal because everything on the outside is right, everything test rite. There's nothing left but internal problems. Ie ring end gap, wrong pistons ect.
Was this
answer
helpful?
Yes
No
Wednesday, September 24th, 2008 AT 8:43 AM

Please login or register to post a reply.

Related Engine Runs Rough Content

Is it Safe to Drive Check Engine Light?
VIDEO
Is it Safe to Drive Check Engine Light?
Instructional repair video
Check Engine Light
GUIDE
Check Engine Light
Why is my check engine or service engine soon turned on? In this guide we talk about what this is associated with this notorious light, what it is used for and what you...
VIEW MORE

Sponsored links