boost spike or surging

[lewisweller]

On 22/01/2017 at 6:10 PM, jbwhiton said:

I wanted to chime in and echo the similar results. I have a tune as well, and all new Denso IK20 plugs, which helped the low RPM stutter from 1-2K rpm. All new vacuum lines to the DV's. Had surging under full throttle and the idle dip as well, and a rumbling rough idle when warming up. Pulled the right fuel pump fuse and ran on the left and all symptoms were gone. Almost no idle dip, no surging, and almost no perceivable( very slight) stutter down low. 

Thanks for your input. 

What did you find wrong with the right pump? Did you fit a new one after? 

After changing the right side after also the left I can hear the right side is noisy, a rumble I hear. 

May need to get back in the tank and see if something isn't correct. 

 

My old pumps were quiet. 

 

 

[lewisweller]

Just to update this post, the new fuel pump left and the right side did NOT fix the hesitation and stutter. It always comes back when hot and heat soaked running. 

I have recently suspected the newer coils (fitted 8months ago and 10k km) may have some issues. When I installed the old cracked coils the problem was the same symptoms but just worse misfire under load. Testing them for resistance across pin 1&3 gave the attached ohms reading and newer coils 1 2 & 3 are suspect for hight ohms and 2 is melted on pin, as per picture. 

I now intend to replace 123 coils and retest.