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Press Gas, hesitation, stall...

50K views 28 replies 12 participants last post by  barchefdaddy  
#1 ·
Anyone had this experience. Noticed it recently when I presss the gas pedal down quickly, it hesitates for a sec or 2 and then you get full power burst.

Today, I pressed the gas, and it just stalled. Restarted no problem, but I feel the hesitation when taking off from stop.

Any ideas on where to start with this one...:dunno:

I have replaced CCV, Plugs, Checked Coils.
 
#9 ·
For anyone installing a C{PS for the exhaust side same yourself a lot of time. When I did mine I was lazy and didn't want to remove a lot of stuff for access. I disconnected the sensor near the Vanos and then tied a string to the end. I then disconnected it at the MAF area and gently pulled it out with the string tagging along. When it was finally freed I untied the string from the old sensor and tied the string to the new one. Pulled the string back out and connected sensor at either end. Worked like a charm and took about 15 mins.
 
#10 ·
I have had an issue with CPS with another car and the symptoms was hard start. I don't have this per se as it starts ok. It like you press the gas and nothing happens, then you get a burst.

Idle control valve is an expensive part. I am going to check for leaks as a start.
 
#12 ·
I was looking through the threads again and found one that discussed the DISA failure. I had sealed this up on an earlier occassion when I did the CCV, but decided to have another look.

I pulled it off and the seal it looked like it was sealed ok. I was taken a closer look on the flaps and noticed wear/melt of the flap on the edge. Then I worked the flap to the point and noticed that the rim plastic was split on the pivot point causing it to lose shape when it was fully open. Will take some pictures.
 
#16 ·
It might be your DISA and/or it might be your Vanos. The DISA varies your intake length and I'm not sure why it would cause your engine to stall or hesitate. A failing DISA should result in suboptimal combustion (reduced power & economy). A failing Vanos will mess up valve timing and can cause hesitation. When I replaced my Vanos seals, my hesitation disappeared.
 
#17 ·
I am going to do the vano's /besiean procedure in a few weeks. In the interim, it looks like I need to replace this part. The economy/power is definitely off from what it was, so will report back once I install the disa.

Any suggestions on where to buy the DISA, seems pricing is pretty much the same across suppliers.
 
#22 ·
While researching and reading disa posts there was a number citing parts that could fall into the intake. There were a number of pictures of broken flaps or parts outside of the space were the DISA sits. It looks like from this picture, that the pin is not likely to fall into the intake unless it falls inward or falls out in the channel as a result of pulling the disa out.

I will report back on how it works tomorrow.
 

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#24 ·
Me too I experienced a hesitation but I was cruising around 75 mph. All of a sudden, the car hesitated a few times - felt like no gas was going to the injectors - car was cruising uphill. Then nothing, everything went back to normal, no more hesitation. Home, I checked the codes, had none. A week or so after the incident I changed the DISA. Never had that symptom again. Not sure if it was because of the DISA, but who knows?