whats up guys... im having a issue with my 98 civic. its b20vtec swapped converted to obd1. The issue i am having is the car is stumbling at idle futuating too 1200 rpms to 500 and feels like it wants to stall, everytime it stumbles the a/f gauge jjumps too.... its also running lean according to the A/F gauge. its a lil eratic when warming up...... i have a cel for the 02 sensor heater. i measured the tps votage at the ecu and sensor and it checked out. i also cleaned the iac and it did nothing.... does anyone have an idea what could be causing this problem???? is there any ohms specs for the factory tps????

 

what model civic is this? and which injectors did you use? And also you should always start with the cel. if its throwing a code for o2 sensor heater you need to check that the heater circuit has power to the o2 sensor. then check resistance across the heater circuit of the o2 sensor to verify its bad.

 

It's a dx model and as for the o2 I'm
Going to check It today..the cel light was on before this issue started though..

 

Oh and stock injectors

 

y7 injectors or b20 injectors? the y7 injectors are smaller than the b20s and that will give you a weird idle and the car will run like junk. I ran into a similar issue when I swapped a 96 civic dx. They are rated at 180cc.

 

There b series injectors and the car has been swapped for a year now I just started having this issue, I also noticed today when I was driving at a steady rpm it miss fired a couple times the problem is intermittent... I'm stumped because i only have a light on for the o2 and I never came across any cars running like **** with a bad 02

 

The power feels like it still there at wot the a/f goes up but at normal driving or idle it says its running lean

 

I have. When you are wot the ecu doesn't look at the 02 sensor. The o2 sensor is used at idle and at cruising to determine if the vehicle needs more fuel or less. A bad o2 sensor will send false readings and give you hesitation while cruising and at idle and give you a misfire. Start with the obvious

 

Ok I'll get a new hopefully it fixes it .. the cel was on before for this and I didn't have this problem .... Would there e anything else causing this ??? I just started the car and its reading lean but every time it misses the a/f goes up to stoich!!

 

The car also stalled on me at a red light

 

What kind of A/F meter are you using? If its the autometer type throw it away because its only good for a light show.

 

What ECU are you running???

 

Lol that is the one I have but that Dosent solve my issue I'm running a p28.... Someone looked at my car yesterday and said my tps is bad.....i unplugged it and it didn't change anything but i did test the tps voltage and it checked out

 

I bought a map sensor and a new tps but haven't put them on yet.

 

**update** I changed the tps sensor and the car stopped stumbling and is way more responsive to the throttle.... But it's barely reading lean still I wasn't having this problem before even though I had a cel for the 02 can anyone help me out ??