Hey its been awhile since I've been on here busy at work and working on my car. So this winter I took my engine out to rebuild it ended up putting lunati voodoo cam with Edelbrock Estreet heads with 1.6 rocker arms shaved the intake 180 thermostat and long tube headers to straight pipes. Ya she sounds amazing well I got it running good then one night out driving the coil pack burnt out found out the ignition timing wasn't right an also didn't know you had to disconnect EST to set timing well got that done ran pretty good after replacing coil pack an setting the timming then all of a sudden it's running like crap multiple misfires pulled the plug all black an some covered in gas so I cleaned them up put them back in and started fine but still misfires the only code I am getting is 33 high low voltage to map sensor i just replaced that less then a year ago everything checks out on it so I'm trying to figure out what's going on is my computer bad do I need to get a chip since all of my upgrades I've read somewhere that could be a problem that the computer doesn't know what to do so it's flooding itself I'm just trying to see if I need to check anything before buying a chip.

 

put these questions in the c4 section they have the expertise....

 

If your injectors are flooding the motor ,I would look into the front coolant sensor.thats the one that talks to the computer.

 

Have you checked for error codes stored in the computer?

 

When you have a scanner connected to it...what is your MAP voltage when idling????

Also will need to know your COOLANT TEMP...AS it reads on the SCANNER.

DUB

 

i had my scanner hooked up it was idling like crap 600 - 650 rpm the map V was from 3.34 to 3.64 the knock was between 34-45 coolant temp was 82 degrees
then idle started to get better 750 to 775 rpm. map V was 2.58-3.34. coolant was 158 degrees and knock was 0
then out of nowhere the idel spiked up to 1075-1100 rpm map V was 2.30-5.00. knock was from 0-45
it was all over the place

 

I am SO GLAD you have a scanner.

I am looking at you MAP voltage. I like to see the MAP around 1.40Volts...at idle.

What is your TPS at idle??? It should be at .525 volts +/- .075 volts

You INTEGRATOR value also???

Can you hear the IACs sucking in air lick crazy????

DUB

 

well as of yesterday it stop running and didnt have time to mess with it so today i went out and messed with it and it will only run when you pour gas in the injectors and yes i can hear the pump prime before i turn the key all the way i had just replaced the pump with an acdelco a year ago maybe and i changed the filler roughly 4 years ago i havent looked at that yet. i did disconnect the fuel line to the injector on the passenger side and turn the key no fuel came out. so is my pump priming but to weak to pump gas or what. at first i thought it was my computer turning off the pump but i dont know now.

 

you need a pressure gauge to know for sure .a pump can go bad any time .

 

You may want to check the small rubber hoses on top of tank, they may be cracked and or the new pump is bad. Anyway you look at it, you have to remove the tank lid assembly. Just a suggestion. Good luck.

 

After I installed a 85 fuel pump and adjusted the pressure it ran for a while then stopped. Turns out the original factory hose burst. See image below.

 

I will write this....I ASSUME nothing at my shop. I would install my fuel pressure gauge set-up and see if I am getting the correct fuel pressure.

YES...that hose on the fuel pump I change out with the bio-fuel hose from OReilly's that is rated at something at or around 220psi. I know it is overkill...but I do not have time messing around with stuff like that.

DUB

 

lets see your fuel pressure set up

 

Will do. I will get a photo up tomorrow.

DUB

 

This is what I made for checking the fuel pressure on the Cross-Fire engines.

DUB

 

Thanks dub .I have a choice I can go with what several others have done and put a pressure gauge inline of the fuel line between the tbs or I could do something like this http://www.bing.com/images/search?q=...9o0&ajaxhist=0 this way I could use a regular fuel pressure tester.I would like to find a way to do it with all metal lines no rubber connections.Thanks again for posting Its good to see others ideas.

 

KEEP IN MIND...that what I made to check the fuel pressure is just that. So it is temporary.

And might I 'say' you ARE thinking correctly as far as I see it.

I ALWAYS have a problem when I have to deal with fuel systems on how the lines or ANY junction is connected. I try to keep that number of connection to the very bare minimum.

I would not use rubber hose like what is in that kit...and that is regardless of the fuel pressure. And the reason is this....I do this for people who may never raise their hood and do ANY inspections. SO...if a hose is leaking for some odd reason...any problem could be considered MY FAULT.

I do know how I would do it...and it would require Silver solder and a 'T' fitting where the test port in that kit you posted...could be threaded in that 'T'...BUT...On the 'run' of the 'T'...the steel lines would be silver soldered in place....and KNOWING that that line would not move due to being joined to EACH throttle body...it is not like the sliver solder would let loose.

PM me if you need to talk or help or possibly a company that I know could do it for you if it is out of your skill level. I have sliver soldered so many custom fuel systems it is nothing but time, patience and getting 'things' right.

DUB

 

http://www.ebay.com/itm/Russell-6392...tVAv78&vxp=mtr this to the y block