Alrighty guys, I did a MPFI swap recently, and the car is hard to start. When I crank it, sometimes it starts right up, but most the time I have to crank it for about 5-10 seconds before it will stay running by itself. When it is running, it seems to be burning rich, but the problem is that when I give it gas or rev it up... the car will start to bog down and then eventually it will die. The injectors were good and didn't look clogged, the timing hasn't been adjusted yet, but will be soon. Does that sound like it could be plugs and wires??? The TPS has been calibrated to .47 on the MPFI manifold, the distributor has been replaced with the SI distributor. I did have to replace the throttle cable to the SI throttle cable, and it wouldn't start once before because the cable was too loose, could that be part of the problem? The ECM is no longer throwing codes after recalibrating the CODE 7 TPS SENSOR..... NO vacuum leaks, checked with brake cleaner

CAR SPECS:
1991 CIVIC DX HATCH MPFI swap, header, cat, intake, no muffler
D15B2 (Stock DX ENGINE)
NO TACHOMETER (DX MODEL)
TIMING hasn't been adjusted yet
NEW PLUGS NGK (from dealer)
stock DX plug wires.. do thoes need to be changed to SI??
SI manifold/intake all that stuff
PM6 ECU - NO CODES

NEED HELP ASAP!! THANKS

 

Well.... there is now more to my endless saga!!! I went out today tried to check the timing. BUT a new symptom. The car seems to be flooding out before it can reach operating temp. It idles extremely slow and quiet. I fired it up and even without an exhaust I couldn't tell it was running. I checked the plugs and regapped them to spec, hell they're brand new plugs. I don't know about the wires though, they were on the car. But here's the deal. When I give it gas slowly, it smooths out and speeds up, but as soon as I take my foot off the gas it starts wanting to die again. Any ideas?? I can't get to the timing adjustment because it will die before I get the gun aimmed and stuff. Is it possible the spark plugs aren't in deep enough or what??? Two out of the four had some carbon build up on them from the previous runnings trying to figure this problem out and the others did smell of gas but no carbon.

 

Sounds like a wiring issue.

 

any ideas on where or what??? I double checked everything for wiring, all wiring was soldered and done carefully. any ideas????

 

Are all your wires right ? Are you positive they are ? How does the car idle when it does start up, is it a rough idle ?

 

it takes a while before it finally gets spark. Once it gets spark it idles very slowly it seems and very sluggish, once it gets air into the mix it seems to run almost normal. On another forum someone mentioned the fact that it could be the AIR temp sensor on the back of the manifold causing it to run too rich. This kind of makes sense since the weather is a bit cooler today than last time it was fired up. My problem is that I have a manifold from a CRX SI I believe and the temp sensor has a plug running off of the back of it. If you need to see pictures let me know so I can send some to my website and link them here. This sensor is NOT wired into the ECU or on the DX wire harness anywhere because I don't know where if anywhere that it is supposed to tap into.

 

if its doing what mine was which was flloding all the gas into the exhulst and pooring out the muffler and also filling my oil pan up with gas and other stuff too , it was my fuekl injectors staying open and flooding the engine , i replaced them and the car runs like crap now , but ti runs , i also have 247911 miles on stock without rebulid , but its ok i got a new motor and tranny to be put in

 

no i am pretty sure it's not the injectors. they are cleaned of carbon and residue with new injector seals and all. I had a problem previous with a cracked injector and replaced them all out of a spare fuel rail i had. i think maybe my throttle body is sticking???? any ideas on how to test that???

 

How is your tps sensor, is it adjusted correctly ?

 

thats what im thinking to it could be the tps what other mods have you done to your car recently?

 

TPS reads fine at voltage levels, has been replaced and recalibrated correctly as stated above this is the first major mod done was the MPFI swap. Other than that it's all exhaust which wouldnt have anything to do with the flooding. I actually messed with the throttle cable and got it to stay running, i think my Throttle body might be sticking because i have to close it manually and then the idle goes back down