Notices
86-95 Trucks & 4Runners 2nd/3rd gen pickups, and 1st/2nd gen 4Runners with IFS

90 4Runner post engine rebuild questions

Thread Tools
 
Search this Thread
 
Old Jun 30, 2014 | 05:14 AM
  #1  
BigBoox's Avatar
Thread Starter
Registered User
 
Joined: Nov 2013
Posts: 16
Likes: 0
90 4Runner post engine rebuild questions

Thoughts and comments requested.

Put a rebuilt 3VZE in my truck, or is it a car?, and immediately got hit with Code 52. It was still at the shop, so he replaced the Knock sensor wire, hoping that was the problem. Started it up, same code. opened it up, replaced the new knock sensor (that came on the rebuild) with the Original KS, and mounted it on the engine lift hook. Still have the code, but, the engine does not go into a "limp, or safe" mode.
Mechanic was perplexed, but he said it was running good, timing shows no malfunctions at highway speeds, so I took it out and have driven it 600 miles now with no perceivable problems.
My question is, why? I have an always on check engine light, no noticeable reduction in performance and while I didn't have 500 miles on it after I bought it before the head gasket meltdown, I actually don't have a lot of miles under my arse with this vehicle.
My second question is what is acceptable gas mileage with this beast? My third question is what can i do to possibly improve on the 14-16 MPG I presently enjoy(?)
BTW, I spoke with a former Toyota Service manager(we're related), who, after listening to the above, with slightly more detail, suggested a piece of black tape over the light.

Boox
Reply
Old Jun 30, 2014 | 06:21 AM
  #2  
scope103's Avatar
Registered User
15 Year Member
 
Joined: Sep 2007
Posts: 8,380
Likes: 871
From: San Francisco East Bay
Originally Posted by BigBoox
... Still have the code, but, the engine does not go into a "limp, or safe" mode.
... I have an always on check engine light, no noticeable reduction in performance ...
What "should" happen is significantly retarded timing. But if your base timing was set up too far advanced, you might have accidentally split the difference and ended up with something that worked. It's not a long term solution; if your broken (or shorted) wire jiggles back into place, you'll end up with ignition so advanced it will probably stop running.

By the way, while there are some who suggest that mounting the knock sensor to the engine hook could work, I just don't believe it.
Originally Posted by BigBoox
My second question is what is acceptable gas mileage with this beast? My third question is what can i do to possibly improve on the 14-16 MPG I presently enjoy(?)
First, measure carefully. I get 20mpg hwy, 15+ city. Second, SLOW DOWN. I drive around 61mph on the hwy, and easing it up to 65 costs about 10%. But it's your choice.
Originally Posted by BigBoox
... I spoke with a former Toyota Service manager... who ... suggested a piece of black tape over the light.
Either he (she) is pulling your leg, or inadvertently disclosing why he (she) is a "former" Service manager.
Reply
Old Jul 13, 2014 | 07:38 AM
  #3  
KingsShadow's Avatar
Registered User
 
Joined: Aug 2012
Posts: 60
Likes: 0
I never relocated the knock sensor to the engine hook. I always made an adapter from a ford transmission line brass fitting and cut it down so the knock sensor would fit into that and the head. What I do know is that on the 3vze it is recommended the original knock sensor and wire be replaced during the rebuild with new ones. Still having problems it might be in the wiring.
Reply
Old Jul 14, 2014 | 01:33 AM
  #4  
BigBoox's Avatar
Thread Starter
Registered User
 
Joined: Nov 2013
Posts: 16
Likes: 0
Thanks for the responses guys. With just over 1000 miles on the rebuild, the longest trip has been to central NY, and the mileage, at 65-70mph on the interstate, and max of 60 on the state highways averaged 16.
As to the timing, it is at Factory specs, And as to the "black tape" comment, the author is also the author of several Toyota service recommendations and is recognized by Toyota dealers for some other innovations. I respect his opinion, based on his qualifications, without reservation. Besides which we're related.
As an aside to my previous comments, I did notice what seemed to me to be excessive downshifting form the transmission at the previously mentioned highway speeds. My normal daily driving is about 10-15 miles, in to town for coffee and some errands, back home and parked for the day. (I'm retired) Since the rebuild, the longest trip was about 100 miles, and the terrain around me is pretty flat. (St. Lawrence river Valley).
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
GreenLion
84-85 Trucks & 4Runners
2
Jun 7, 2021 10:49 AM
ZONAYODA
86-95 Trucks & 4Runners
11
Jun 30, 2015 05:36 PM
Niameyrider
Offroad Tech
0
Jun 25, 2015 05:50 AM
yamaha73
86-95 Trucks & 4Runners
10
Jun 18, 2015 06:19 PM
bobbybouche
86-95 Trucks & 4Runners
0
Jun 18, 2015 10:22 AM




All times are GMT -8. The time now is 11:29 PM.