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Old 04-08-2016, 07:32 PM   #1
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Default Hesitation and erratic AFR under part throttle

Hi all from the UK

Recently turbo'd my MX5 using a MSPNP Gen1

All was well during tuning on the dyno but on normal running the car hesitates and the AFR goes all over the place on part throttle.

On full throttle the AFR stays perfect and same goes for off throttle.

It has a BMW E36 VTPS and the modification of adding the two wires and removing R6 and 7 I have just found has already been done.

When I notified the Tuner he suggested change plugs so I changed them for NGK ....7. (The correct ones for a turbo MX5)

Any ideas as to wether his is a tuning issue or a physical issues would be greatly appreciated!

Other info:
Tuner has a good reputation for tuning with mega squirts in the UK and helped my wire in the VTPS as the voltage appeared to go the wrong way when calibrating the TPS.

New Bosch 550cc injectors.

9 PSI boost on a TD04

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Old 04-09-2016, 07:06 PM   #2
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Post the msq of your tune and let someone check it out.
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Old 04-09-2016, 07:12 PM   #3
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did you calibrate the TPS and tune your TPSdot enrichments correctly?

and I dont understand removing R6 and R7.

R6 is part of the barttery voltage circuit and R7 is a pull-up resistor for the CLT sensor...

MS is designed for vTPS, there is no internal modifcations that need to be done in order to accept it.
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Old 04-09-2016, 07:38 PM   #4
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Wromg thread
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