cant remember if ive posted about this before or not. but my car has a huge problem and im running out of patience and ideas on fixing it. the short end of the story is that its a huge stumble/hesitation that developed about a year and a half ago. i stopped driving the car shortly afterwards cuz i had no money to fix it. started after a header install that deleted the smog stuff but kept a high flow univ. cat (that is now cut off). it nearly dies at any throttle position above 1/4 throttle. if you rev it in nuetral its decent but not entirely as bad as in gear. last night i put in a walbro 255lph pump thinking the pump was shot and that didnt fix the problem.

under normal driving, you cant tell theres a problem. its when you get on the gas that theres a problem. after filling it up with some gas, i got on it in first and it kicked the *** sideways but then almost completely died. it happens the same way. if you roll into the throttle it slowly does it. if you just slam the pedal down it nearly dies and you have to nurse it along till you can even driving at a normal speed.

parts ive replaced within the 2 yearslugs, wires, cap, rotor, map sensor, o2 sensor, egr valve, fuel filter, fuel pump, tps sensor. fuel pressure is set to 42psi with the car off but the key to run. where else should i look? i really need help here guys.

 

what does the fuel pressure look like when you floor it & it acts up?

 

i havent been able to check that. i dont know if its my fp gauge or what but i cant hook it up with the map sensor and map sensor bracket installed on the intake. is there a better option to get at a parts store that will work with it attached?

 

You can have your MAP Sensor not bolted in and still have the rubber hose attached to the plenum. I've done it with my car to check the FP while driving. Just tape the MAP Sensor bolt to the bracket (so you don't lose it) and tape the FP gauge to the windshield.

 

Check all injectors for proper impedence and check injector plug connectors for any loose wires.

 

One word ............. "Scanner"

You need to scan the car while driving it. I recommend datamaster. This will give you major insight into your problem.

Just my

 

ok well i checked my injectors tonight. i read someplace on here that the stock ones are supposed to be between 15-18 ohms. most of mine were in the 16.0-16.5 range except for number 5. it was 5.1 ohms. im betting thats my problem. im also going to get new MSD 8mm plug wires as the taylor spiro pros i have now are burnt (but dont visually arch as of right now) from my primaries. im going to run them under the headers for cleaner look and safer wires.

as far as scanning the car. i have a laptop to do it with but need more info. i think the search feature is still down, what should i get for that? the laptop is an older Gateway 2000 with NO USB ports. they are all serial ports.

 

Hopefully that #5 injector is the root to all your problems. Make sure you check the injector connector for loose wiring the injector may still be good.
Good Luck!

 

when i checked the injectors, i pulled the connectors off and tested the injector itself. but im going to inspect that connector for any damage.

 

I prefer the serial ports myself, USB's can try your patience sometimes.
Check the net for "WinALDL", there are diagrams for constructing a cable. Two types, one is easy to do with a quick trip to the Shack and an hour of soldering the parts together.
Definatly build or buy one (they're pretty cheap to buy too)
Try out the Datamaster software (Get the $8D version for your car) Do some logging and watch what is happening.
The problem may also be with your IAC not being reset and componding the injector problem.

 

Get a new injecotor . See what happens next . At first I was thinknig a siezed IAC vlave would do what is happening . But you got one bad injector . THAT would do'r