Power Cuts Out on Hwy then Comes Back On

[MiniBeast]

Close to having my '61 Austin Cooper with a Minitec 20B/16B Vtec fully road worthy. One major problem is that while driving between 60 to 80mph the power will cut out then after a second or two will come back on. Also if I punch it at these speeds I will get a sudden burst of acceleration followed by the big power loss! Very dangerous on CA Hwys!

My setup is all Minitec with a OBD1 CPU wired to a Minitec harness wired to an OBD2 harness wired to the engine.

The CPU throws a dash and seven blinks which I think is fault code 17, Vehicle Speed Sensor (VSS)?

Considering all the wiring mistakes Minitec allready made it could easily be wired wrong or not at all. Oh and Minitec is not very helpful at figuring out any of their caused problems.

Any ideas on how to make this problem go away?

Thanks, Carl

[Furyof4]

I would pick up a factory manual from here ->http://www.helminc.com/helm/welcome_...224&Style=helm

It will show how to diagnose your code properly. It is most likely a wiring issue. Also, what ecu are you using?

[Pepper]

MiniBeast:

Could be fuel starvation, return could be too close too pump in tank; w/ external pump: suck hose collapsing, or sucking air, junk in tank & the fuel filter ?
Fo4 -Hey
-Pepper

[N. J.]

The CPU throws a dash and seven blinks which I think is fault code 17, Vehicle Speed Sensor (VSS)?


Any chance it might be the vehicle speed sensor creating the problem?

N J

[250ptm]

Code 17 is VSS sensor on the odb 1 ECU. It is one long flash followed (with no break in between) by 7 short flashes, which pauses and repeats if it is the only code.

VSS sensor loss of signal will inhibit the vtec engagment, at the speed you were travelling it would be close which may explain the sudden apparent power loss.

if you dont post the code during normal driving at lower speeds, it is likely an intermittant connection (maybe due to vibration) between the ecu and vss (or speedo and ecu if you have an autometer gauge) Some models of Autometer gauges have a connection on the back for ECU output this wire should run to pin B10 on the ECU.

Jack the left front wheel clear, ign on, (engine off) measure voltage at pin b10 and ground while rotating the left wheel should read around 5.0v dc (pulsing 0 to 5 approx) if the VSS is good. There are more checks in the Manual which can be followed.

[MiniBeast]

Hi all,

I had my Vtec guy - Nickolas Upton go through the wiring today and he said that the connection is from the sensor to the cpu (after he played with the wires for quite some time). We then took it out on a run and it didn't cut out at speed (although todays temp in the bay area was cool, if that could have anything to do with it) actually got up to 85mph (over 5000) with Vtec still ingaging with no trouble so maybe he jamed some wires together while testing them! Oh and before when it was happening it only happpened in 5th on the freeway. 6500 rpm in 3rd or 4th with Vtec had no cut out. Today even after reset it still through code 17 BUT the Vtec is working!!! In therory VSS 17 should not allow Vtec to come on but it is - as I try to keep the Mini on the road!

Nick has checked my fuel system and says all is good, I'm running 3/8ths hard fuel lines in and 1/4" lines out with the MiniTec recommended fuel pump.

Could be the VSS sensor and will try 250ptm's way and if that doesn't work then I will find a proven VSS and see if the code goes away.

Thanks for the help guys, can't believe how insainly complecated a Minitec conversion can be (if only they let on in the tinyest bit). Now back to all the freaking front suspension problems, ugg

Carl

[Tavis1]

What suspension problems?

[MiniBeast]

The problem turned out to be one of MiniTecs VSS wires went in to one connector in the green plug (before the CPU) but came out a different one! Doh After fixing it I took it out for a run to 95mph in 5th and also hit 7k rpms in 3rd with no fault codes! Yea

OMG want to be driven insane? Buy a Minitec MTB2 full set up! The amount of problems has been endless and I'm not over exagerating. But you want to hear about the suspension: First off I'm on the 3rd set of lower arms from MiniTec and the RH side arm still hits the tranny drain plug! (At least I can turn - which I couldn't do with the first 2 sets). On both sides with the tires on 13x7 wheels, rub the upper arms when making a full turn. Both of these problems I will have to live with.

Right now I'm waiting for 350lb 10" springs from MiniTec to replace the 300lb ones because the tires still hit the Zeemax flares with over 1/2" preload on the springs (and I'm running 6.5" of ground clearance and 3+ fingers clearance from tire up to flare). The preload causes the springs to make a cresent moon curve from lower arm to top bracket and also has the springs rubbing the shocks AND upper brackets. Makes for a really annoying noisey ride.

With out going through page after page of problems with the MiniTec setup all I can say is that my now $30K '61 Austin would never be running without the services of Nickolas Upton (Vtec/Mini extrodinare). Out of the claimed 350 MiniTec conversions sold I would be highly surprised if more than 25-50 are actually on the road without major problems. I should mention that mine has a stock nose which means with a 20B there is 1/8th inch or less clearance EVERYWHERE and that includes custom shims to lower the engine height in the bay. Shoe horning the engine in (multiple times) is no easy task and I do not recommend it in a stock nose.

I'm truely amazed that after all the kits they have built and sold that when it comes to mine it is like this is their Beta version.