2006 captiva ecotec 2.4 This is gonna hurt us

Hi everyone,

Although i have not received this one yet. I am anticipating a pain in my bottom. Anyway the owner is a really nice friend and i am gonna take the challenge.

My friend complains the engine is shutting of in highways or at anytime

I have dealing before these engines and untill now problems are related to VVT actuators, chain tensioner, chain guides, bad grounds.

I have pulled some PID's and DTC's. At that time engine turned off twice, but before that air flow readings (MAF) was jumping from 2 to 8 g/s (@ 650 rpm).

I have attached a screenshot of DTC.

The main question is, how many different problems do you see?

Hi guys,

Today i received it. The first thing i checked, was DTC's. Not only has the ones posted before, but to many others.

Exhaust vvt actuator was open. I replaced it and cleared everything. Now is when the things become interesting.

Now the engine is not making strange noises like when had the bad vvt, but is still setting P0097, P0107, P0113,P0192,P11C2 & P2228.

Two conditions were detected

1. The engine turns on normally with smooth idle, but some weird readings (no AC, no lights, no anything but idle):
MAP: 45 Kpa (normally should be 28 - 30)
MAF: 4.93 g/s (which i think should be near 3)
Calc. load: 55.29% (which should be 20 - 25)

2. The engine suddenly hesitates 2 or 3 seconds and then shuts off.

Sometimes upstream O2 sensor stays rich (1.28volts) and sometimes is fluctuating pretty normal.

I forgot to mention that spark plugs were completely white and due to many of those codes are related to low input sensor, i checked MAP voltage as reference:

Vcc: 5.01 vdc
Signal: 3.19v @ 81 kpa & 1.66v at 42 kpa
Ground: 0.01volts

Hi guys. Today news,

I decided to focus on the two conditions mentioned in my yesterday post (smooth idle & hesitstion until it shuts off)

When hesitation occurs, MAF, MAP, and Calc load jumped in an erratic way. But those could be sympthons of hesitation and not the root causes.

Ecu decide today stay in open loop and MAF, MAP and Calc load back to normal (MAF: 3.12g/s - MAP: 31 Kpa - Calc load: 20%)

I noticed that O2 sensor also decided not to work anymore staying at 1.28v (which i think is starting ecu voltage in this car). While downstream started at 1.28v and then oscillating, upstream sensor stayed at 1.28v. I finally checked for a good o2 heater circuit operation and is ok. (See picture).

I have ordered o2 sensor.

Any comment, will be helpfull. Thanks

Hmm id go to the oxygen sensor connect and use a test light to ground and see if you can pull that 1.28 volts down.. then id replace the sensor if it does

Hi cookie,

I'll do that.

Thanks

Hi guys,

It finally was not as hard as i was expecting.

O2 sensor was reporting to PCM a rich condition (1.28v). Then gases were being heating excesively exhaust manifold.

I found exhaust manifold broken, which i think was sufering excesive high temperature (besides it has a low thickness area, compare to others).

Hesitation and the engine shutting off was due to pcm trying to control idle with a bad O2 reading (sometimes working and sometimes fluctuating).

The codes related to low temp, low rpm, low barometric press, were set when engine stalling.

I think is a fix. Thanks to all of you who took time to read and think about this topic.