unplugged injectors ( need some clarifications)

[RayBan GST]

dear all,

well i am having a difficult time in driving my car its sputtering and backfiring when iam below 2500 rpm , and it does that all the time but once i am over 2500 rpm the car drives fine to red line. im boosting fine and i have power.

i changed the spark plugs and the wires ( NGK Irridium ) number 7 but no change , i even cleaned the MAF and the air filter but still no change.

i have a question on the the injectors which i need you to help me with.

the injectors are in this order if you are facing the car from right to left 1-2-3-4 , i have unplugged number one and the car starts to shake which is an indication that its working , i did the same with number 4 and it did the same also .., however for number 2 and 3 there is only a little change in the engine sound not even noticiable is this normal for injectors 2 and 3 or they should give me the same reaction as 1 or 4 ?????????

i know backfiring is a fuel starvation and i really suspect these injectors


any feedback will be apprecaited

thanks

 

[RayBan GST]

i forgot to mention that my isc is disconnected and i have high idle around 1800 k and goes down to 800 with the ac on and stalls , i thought i fixed this problem but no its coming again now its also stalling when the ac is on and its sputtering on low rpm and backfiring i cant drive the car like this

i just bought injectors cleaner and run it with the fuel 98 octane but also that did not help

could it be my TPS??????/ when i disconnect the tps the cell is on and my idle will be very high , do you think its working ?

i need your help guys please
thanks

 

[flinguist]

Why is your ISC disconnected? That could be your problem. This tells you how to check you ISC DSMISC FAQS page . If your ISC was bad it could have also damaged your ECU. This tells you how to adjust your TPS TPS Adjustment

Here is a throttle surge faq that may help you. Idle Surge FAQ

Good luck.

 

[RayBan GST]

Guys again i need your help before i buy new injectors

the injectors are in this order if you are facing the car from right to left 1-2-3-4 , i have unplugged number one and the car starts to shake which is an indication that its working , i did the same with number 4 and it did the same also .., however for number 2 and 3 there is only a little change in the engine sound not even noticiable is this normal for injectors 2 and 3 or they should give me the same reaction as 1 or 4 ?????????

i just need an answer for the above


thanks

 

[Burnett03]

Anytime you unplug an injector the car should stumble and shake, just like how it did when you pulled the others.. Sounds to me like your injectors are stuck CLOSED. Then they free themselves up and run fine to redline. Backfiring is not always fuel starvation. But to answer your question the injectors need to be replaced or cleaned.. Try tapping on them with a wrench and see if they unstick.

 

[RayBan GST]

thanks man

but they are stuck closed or stuck opened ??? how to tell the difference ? cause my gas mileage is really bad????

thanks again

 

[juanpac0]

Don't use iridium plugs, use NGK Copper BPR6ES, also check your plug wires.

 

[RayBan GST]

ngk plugs are just fine, they are gapped and new , however to answer you i did use the copper to check and also i did change the wires but no change.

injectors 2 and 3 when unplugged make little to no difference to the engine idle unlike 1 and 4

 

[snowborder714]

If you're standing on the drivers side looking at the engine, this is the spark plug order.

4
3
2
1

4123


Or from the front of the car, use the image on the left.

You must be logged in to view this image or video.

http://www.dsmtuners.com/forums/problem-diagnosis/10465-firing-order-merged-5-7-a.html