Ok I have hesitations after 4k roughly at 47-4800 rpms and then on down the rpm range every other 500 or so rpms. I have the pill in the vac line to the boost sensor and it has a nice big extra ground on it.

What else can cause hesitations like this?

 

There is supposed to be a pill int he vacuum line to the boost sensor? Is this an S4 only thing, or both S4 and S5?

 

pretty sure ita applicable for all FC's

 

The plot thickens at to the cause of my shitty performance. I don't even know why I am bothering. T2 conversion is less than 2 weeks away.

 

anybody have an idea? : /

 

i actually had this problem w/my 86 na, around 2nd gear..and around that much RPMS...i blame it on my fuel pump/regulator, cuz i was having problems w/it and it wouldnt pump consistant, but i dont know about w/the T2s

 

this problem is on an 87 N/a

 

well im not expert but check if your regulator is in good shape, thats what this shop told me when i brought it in

 

Well I am going to check that out. I have a spare rail here so I will swap that over tommorow. If the problem is solved I know that was it.

 

hahah aights man, let me know too, because i bought the whole SX PUMP/FUEL FILTER/REGULATOR....soo i'll know that my problem will be solved when i put those in

 

Check the connections on both of your secondary injectors aswell mate. Sometimes even if at first they appear ok on closer inspection might actually be totally rooted, case in point my old ones.

 

Will do I will check on the connectors when I take them out.

 

aights i'll check mines too since we seem to have the same problem

 

Since I can't find the damn thing in stock at MT what parts did you get? I may need to go aftermarket if my spare rail doesn't do the trick. :/

 

Clean your injectors, clean your spark plugs, and replace your fuel filter.

 

I hope somebody locally has a filter. I already have brand new plugs.(Got them for the dyno runs) and I have a set of 91 injectors that I am searching for the parts I need to swap while I have the low imp injectors cleaned and rebuilt. : / ahh the wallet is quiverring(sp?) in fear. Oh well. Thats the price for Dyno runs I guess. :/

Santiago

PS- If anyone has alternate causes for this problem let us know.

 

all i bought was the SX fuel filter/regulator/pump, i didnt buy any plugs/injectors, i will later, car is under project, the shop didnt say i needed to replace the fuel rail but it might b a good idea since im replacing everything else, but i dont know wher ei can get an aftermarket one

 

The FPR is not causing your hesitations. The rarely fail, and when they do, it will cause a lot more than hesitations. It is most likely your injectors, ESPECIALLY if you have been running premix. Ive noticed since running premix(over 2 years), the fuel filters dont last nearly as long, and the injectors need to be cleaned regularly. I usually just dump a quart of MMO in a full tank of gas every couple of oil changes, and that takes care of the injectors.

Dont discount the little things. That should always be the first things to be checked, instead of the last.

 

Huh I will see what happens. I am doing the filter if I can find it localy if not I have to wait for nopi or RP to ship. I am also taking some injector connectors and using them for my 91 Injectors and having my old ones cleaned. But I am still going to switch the rails and see if that does anything. Who knows I may get lucky.

 

Problem solved. It was the Boost sensor.

I ran it for a little and it didn't have any more hesitations.


Santiago

Thank god for parts cars!

 

OK problem is now back. I am buying a fuel filter this friday to see if that will do it. I am also going to swap with my spare fuel rail to see if its the FPR. If those two don't work I guess I will send of my injectors when I can cuz I still don't have a spare set that will fit. :/

 

And your Suuuuuuuuuuuuuure its not your connectors? I don't mean to flog the dead horse over this but this is exactly what my car was doing..
would be there.. then not... then come back..

 

Ok I am going out right now to check my secondary plug connectors. I will take some pics brb you guys.

Santiago

 

i would consider the fp (maybe not enough volts?).

I would check on that pill. My s4 TII isn't running one now atleast

i would also check timing also........and like suggested.....just make sure everything is up to snuff.

just throw'n ideas out

 

ok I didn't take pics of all the injectors but hell is 11pm here and I am comming down with a cold Here is the injector connector and plug: