Power loss after conversion

[MyCARneedsHelp]

Well im at the end of my conversion. Just so we can bring this up to date i took everythin off my 88 GT and put it on my 91 LX. The only thing i didnt change was the dash. Now after all this hard work and money im getting ready to just give up. Ive had problem after problem and for some reason it wont give me a break. Its a fully rebuilt motor with some minor mods .... Edlebrock upper/lower manifold,A/C Delete Kit,BBK shortys,Headman H-pipe,American Thunder catback,MAC Cold air, removed stock fan, auto - t-5 conversion just the usual stuff. The problem im getting is after driving for about 30 seconds the car losses ALL power. I replaced the ignition coil,fuel pump relay, solenoid, fuel regulator many many many other parts but im not getting anywhere.... Any way after i lose the power i dont hear the motor running at all and when i step on the gas peddle i get nothing. After a few pumps the car jumps back to life and takes off faster then hell. I double checked my plugs, wires, distributor cap and timing.... what else could cause me to lose power then revive it self? thanx for any input. O and yes i did a search i didnt find nothing

 

[vristang]

I will have to suggest pulling the codes.


I did have similar symptoms in my 2.3L when the exhaust line to the EGR had cracked. The computer was forcing low power.

 

[tmoss]

If it's speed density, you might have a faulty connection (electrical or vacuum) to the MAP sensor or the sensor itself may be going bad.

 

[Paul Perreca]

yea did you convert it to mass air? or did your 91 already have mass air, and you just used that?? Did you change to the A9L computer because of the T-5 Swap?? Could be computer related, if you have an automatic (trans) computer in there, it will most likely have a problem w/ the manual trans... just a few things...
Paul Perreca

 

[MyCARneedsHelp]

Its the speed density computer still and i never changed the computer for the trans before and it ran great. Im gunna double check the MAP and connections. I already checked the vacuum a million times.

 

[MyCARneedsHelp]

ok i tryed to pull codes and nothing

 

[MyCARneedsHelp]

okay i just changed the distributor and checked the electrical connection to the map and its all good . I checked it all with a volt meter and replaced the dis. with a new one and still gave me the same problem. I also noticed that it smells really really bad like gas. Could i be getting to much?

 

[RsStanG1987]

Did you change to the A9L computer because of the T-5 Swap?? Could be computer related, if you have an automatic (trans) computer in there, it will most likely have a problem w/ the manual trans... just a few things...
Paul Perreca

Totaly not true when i converted my car i left the auto computer in there worked and ran just fine. I suggest doing a read up on the 5 speed swap.. Dave opiela

 

[MyCARneedsHelp]

it isnt the 5 speed swap because i did that months ago. I just put the motor and wiring into a donor body. Now im getting bogging/power loss. Its very odd ive talked to 2 different Ford Techs and they cant figure it out eather. I would go carb but im broke so the fuel injection im just gunna have to debug

 

[RsStanG1987]

Are you running the speed density computer with the mass air setup?

 

[MyCARneedsHelp]

no everything is still speed density. I didnt have this problem in my old car for some reason something is screwed up somwhere. I just replaced my M.A.P and STILL doing the same thing. could i be getting to much fuel? i dont have a gauge so ...

 

[tmoss]

Hmmm I was thinking bad MAP - and it's output is ~160hz frequency so you need a frequency counter to check it - but if you put a new one on then maybe you have some leaky injectors or a failing/failed fuel pressure regulator diaphram.

Also, do a continuity check on the wires between the MAP sensor plug and the EEC pin plug to be sure the signal can get to the EEC. Use my diagrams on the www.veryuseful.com/mustang/tech/engine site.

 

[MyCARneedsHelp]

whats a regulator diaphram??? ive never heard of one. I already replaced the regulator it self also when i put the injectors back in i replaced the o-rings and those orange caps. Im gunna check the continuity to & from the m.A.P. Thanx

Also i didnt realize it until now but ive used that site and the diagrams for everything. Thanx so much those are soooooo helpful

 

[jrichker]

No codes and loss of power would suggest an electrical problem. A voltmeter used to monitor the voltage on the igntion circuit, ECC power and fuel pump power would be the thing to do.

Use Tmoss's site for the diagrams you will need, everything is there.

 

[bimmertech]

i'd say check tps voltage if you haven't already done that. then check the throttle voltage while someone moves the throttle real slow and check for voltage spikes or dips in the tps.

 

[04sleeper]

Did you use the old wiring harness to the computer? Or did you use the mass air harness and just hook up the speed density computer to it?
Because there are a few terminals that are different on the mass air harness.

 

[tmoss]

Did you use the old wiring harness to the computer? Or did you use the mass air harness and just hook up the speed density computer to it?
Because there are a few terminals that are different on the mass air harness.

Good question, he said he moved everything over, so I thought that was wiring too.

 

[MyCARneedsHelp]

I replaced the T.P.S yesterday and the idle bypass valve so it shouldnt be those. TMoss I used everything from my old car including the wiring. Nothing on the car is mass air or mass air setup. Its ALL from my 88 gt. I heard of computers going bad so i didnt even touch the computer it self i didnt want to risk shocking it. I used some rubber static resistant gloves from work. Geez this car is getting annoying..... is there a way to check my fuel pump without a pressure gauge? If not how much do they usally cost and where can i get one. ??? ive never had a fuel problem before sorry if that was a stupid question