94h22acord

94 accord lx coupe with a JDM h22 swap. car is turboed and built. its been on the road over 3 months now without any problems. the car is wire tucked with the fuse box from the engine bay ran in to the inside under the glove box. strut tower harnesses were all extended to come inside the firewall to the inside of the car and brought back out through a central location of the firewall behind the motor. the car is also running on hondata s300.

Symptoms:
The car will start fine and run fine when it is cold most of the time.
As soon as it warms up, it has a major miss. the check engine light will come on and the tach will drop to zero, as soon as i play with the gas pedal the check engine light will go off and keep coming back on as i try to fight it from stalling. Then the car might stall; sometimes it might not stall and be totally fine again. Or it will stall and be totally fine soon as i start it again, but the same thing happens as soon as the motor warms up it starts doing this.

Things I've tried:
Replaced the coil, ignitor, cap and rotor because if i pull a plug wire off im showing signs of weak spark (yellow in color). everything checked out fine because i am still getting the same symptoms.

I have fuel pressure but was thinkin maybe a fuel pump issue (Walbro 255lph), but unlikely because the gauge reads fine when the car is freaking out.

Redid all of the battery terminals to make sure i wasn't having ground or power connection issues.

My next plan of attack is to check the ignition wiring under the dash, i used it to steal power for my gauges accessories and whatnot, maybe i have a short somewhere.
Bad ECU?

please please if anyone has any ideas on what this could be or what to check next i would def appreciate it. Thanks in advance

94h22acord

bump

System Lord

iTrader: (1)

throttle position sensor have you re wired this or replaced? if not check that cel when it stays on

94h22acord

when i run the display on the hondata s300 it is reading the correct percentages at 0 and WOT, so im pretty sure its fine. as for the cel, it never stays on or holds a code, it just flashes on until i get off the gas then it goes away.

over the weekend the hondata was reading 7 volts to the computer. this is a new problem tho because since these problems have occurred its always read 14.3 when running.

so i check the battery and it was fine 11.9 volts with the car off. im goin to check power to the fuse box, then power to the ecu when i get home from work.

Mervin

MAP sensor?

Enzo15

Well for one your batt is probably bad. It should be at 12.6 when the car is off. You have dead cells in the battery. Check it by taking out the fuel /ecu fuse and crank the car while checking the batt voltage. It should not drop below 9.6 volts while cranking the engine for abour 5-10 sec. Batteries can cause electrical problems since it is part of the electrical circuit.

jprelude92

could be a short somewhere from all wire tucking that was done. did you splice any wires to make them longer ?if you did i would back to those places and recheck them.

hdragster

I'm having the same problem with my car also after I did the update on hondata.
Let me know what sup...

94h22acord

Im slightly retarted because i thought i had a draw on the battery, come to find i forgot i had the gauges(boost, fuel and oil pressure) that r in my glovebox wired to 12v constant because i was rushing to get the car on the rd a while back. once i rewired all of that stuff there was no more draw on the battery and it holds 12.6 when off so its good.

the splicing checked out all ok on the plugs i extended. the only thing i can think of is a main relay? do accords even have this main relay i read about or is it a civic thing?

i checked power to fuse box it reads exactly what the battery is puttin out. checked power at the ecu and it is stepped down to 12.4-12.5 is this normal? i assumed so, so u dont fry the ecu?

im going to do the hondata update today after work. im crossing my fingers because this is becoming a nightmare and im missing perfect spring driving nights haha. thanks everyone!

94h22acord

it was the MAP sensor thanks melvin

flyrod

The actual sensor was bad, or a wiring problem? Thanks for coming back with the solution.

Mervin

Thx for the update, good 4 the knowledge database for other searchers!

94h22acord

it was the sensor itself, i bought a diy sensor from xenocron 4bar for the boost and something must have went wrong...when it would crank and attempt to run i saw 40lbs of boost on my hondata. we were like WTF? swapped it out with a stock one did a little tweaking with the map and she fired right up. THANK GOD.

yea i posted the solution cause too many times i come on here and people have symptoms and problems like mine and they never repost wat the problem actually was haha. thanks for all the help guys