'95 xj, 4.6l, comp 68-232 cam, 702 injectors @49psi
hello,
It is currently running rich, warm idle is 14.3 afr(wideband), & 22"Hg. After sitting for 3 weeks.
Last month it was running fine would warm idle at 14.6-14.7 afr, was always rich at WOT but that is another story.
I thought it was the Map sensor, cause it was reading low ( 1.2V ) at warm idle FSM says 1.5-2.0 V is correct, however, 3 different units all read the same thing. TPS is new.
With my scanner I can see the narrow band OXy sensor voltage swinging from low to rich constantly.
this is my question, I know a badly spraying injector can cause an increase in fuel consumption as the pcm throws in more fuel in an effort to get the narrow band to give a correct reading, cause the normal amount of fuel is not burning correctly. will this extra fuel cause a wideband (reading before the cat) to show rich. I'm thinking yes i mean it makes sense but is is not something I know. Does anybody else know?
Any other suggestions, I read the FSM to see the inputs the PCM uses to calculate injector duty cycle for warm idle, Engine coolant sensor is good, TPS is new and good, Intake manifold temp is good, map is good as well, oxy sensor "looks " ok, it swings rich to lean.
any other ideas?
Its not a instrumentation problem with the wide band, exhaust smells rich and MPG is $hit.
I need the car for the next 2 days, so don't want to pull injectors, see that "yes they spray shit" then put them back, just to pull them in 2 days and get them cleaned. if/when injectors are spraying well and it is still a problem i suppose it is replacing the narrowband oxy sensor, it is a NGK, 7 years 20,000 miles (tops) old, it *should* be fine.
Any suggestions?
running rich.
-
- I think I'll order a "tab"
- Posts: 44
- Joined: March 30th, 2011, 5:00 am
- Stroker Displacement: 4.6
- Vehicle Year: 1995
- Vehicle Make: Jeep
- Vehicle Model: XJ
running rich.
Obd1 scanner.
'95 sport,4.6 stroker, 4.5" lift, 32"s, 4:10's, 8.25&SYE, taurus fan
Sydney Australia
'95 sport,4.6 stroker, 4.5" lift, 32"s, 4:10's, 8.25&SYE, taurus fan
Sydney Australia
- Cheromaniac
- I live here
- Posts: 3190
- Joined: March 8th, 2008, 12:58 pm
- Stroker Displacement: 4563cc
- Vehicle Year: 1992
- Vehicle Make: Jeep
- Vehicle Model: Cherokee
- Location: Cyprus
- Contact:
Re: running rich.
Are you sure you have the 702 injectors and not the 703's? The 702's flow only 21.0lb/hr at 49psi whereas the 703's flow 24.1lb/hr @ 49psi.rainman wrote:702 injectors @49psi
With the 702's I'd expect your engine to be running lean. However yours is doing the opposite and the MAP sensor reading is low, so I suspect that you have a vacuum leak somewhere.
1992 XJ 4.6 I6 - 5MT - Stroker build-up, Stroker "recipes" Sold
1995 Mustang GT - 4AT - Modded Sold
2006 Mustang GT - 5MT - Modded Midlife Crisis Car
1995 Mustang GT - 4AT - Modded Sold
2006 Mustang GT - 5MT - Modded Midlife Crisis Car
-
- I think I'll order a "tab"
- Posts: 44
- Joined: March 30th, 2011, 5:00 am
- Stroker Displacement: 4.6
- Vehicle Year: 1995
- Vehicle Make: Jeep
- Vehicle Model: XJ
Re: running rich.
yep typo 703 injectors.
hmm vac leak you say. i will have a look. Ta.
hmm vac leak you say. i will have a look. Ta.
Obd1 scanner.
'95 sport,4.6 stroker, 4.5" lift, 32"s, 4:10's, 8.25&SYE, taurus fan
Sydney Australia
'95 sport,4.6 stroker, 4.5" lift, 32"s, 4:10's, 8.25&SYE, taurus fan
Sydney Australia
-
- I think I'll order a "tab"
- Posts: 44
- Joined: March 30th, 2011, 5:00 am
- Stroker Displacement: 4.6
- Vehicle Year: 1995
- Vehicle Make: Jeep
- Vehicle Model: XJ
Re: running rich.
so looked for a vac leak.
used carb cleaner to spray around the manifold at idle to see if the revs picked up. nothing.
built a smoke unit to smoke the manifold -no smoke coming out of the manifold.
Vac is 22"hg @ warm idle. I'm thinking there is not a vac leak.
Injectors flowed the same and had good pattern.
had to order a new trany mount from rock auto. so bundled it with a new NGK oxy sensor. Should be here next week.
Any other ideas? suggestions?
used carb cleaner to spray around the manifold at idle to see if the revs picked up. nothing.
built a smoke unit to smoke the manifold -no smoke coming out of the manifold.
Vac is 22"hg @ warm idle. I'm thinking there is not a vac leak.
Injectors flowed the same and had good pattern.
had to order a new trany mount from rock auto. so bundled it with a new NGK oxy sensor. Should be here next week.
Any other ideas? suggestions?
Obd1 scanner.
'95 sport,4.6 stroker, 4.5" lift, 32"s, 4:10's, 8.25&SYE, taurus fan
Sydney Australia
'95 sport,4.6 stroker, 4.5" lift, 32"s, 4:10's, 8.25&SYE, taurus fan
Sydney Australia
-
- My keyboard is getting warn out
- Posts: 1032
- Joined: February 28th, 2008, 3:13 am
- Stroker Displacement: 4.9
- Location: Michigan
Re: running rich.
have you verified it`s going into closed loop ?
- Cheromaniac
- I live here
- Posts: 3190
- Joined: March 8th, 2008, 12:58 pm
- Stroker Displacement: 4563cc
- Vehicle Year: 1992
- Vehicle Make: Jeep
- Vehicle Model: Cherokee
- Location: Cyprus
- Contact:
Re: running rich.
You've definitely ruled out a vacuum leak. O2 sensor would be my next suspect so hope that works.rainman wrote:Vac is 22"hg @ warm idle. I'm thinking there is not a vac leak.
Injectors flowed the same and had good pattern.
had to order a new trany mount from rock auto. so bundled it with a new NGK oxy sensor. Should be here next week.
Any other ideas? suggestions?
The MAP sensor definitely ISN'T at fault as a reading of 1.2v would be normal at 22" Hg vacuum (i.e. 8" Hg MAP).
-
- I think I'll order a "tab"
- Posts: 44
- Joined: March 30th, 2011, 5:00 am
- Stroker Displacement: 4.6
- Vehicle Year: 1995
- Vehicle Make: Jeep
- Vehicle Model: XJ
Re: running rich.
yes its is going closed loop, the oxy voltage is bouncing high then low consistently, it is hunting around its value of 14.2, its working its just not hunting around 14.7afr.
Obd1 scanner.
'95 sport,4.6 stroker, 4.5" lift, 32"s, 4:10's, 8.25&SYE, taurus fan
Sydney Australia
'95 sport,4.6 stroker, 4.5" lift, 32"s, 4:10's, 8.25&SYE, taurus fan
Sydney Australia
- Cheromaniac
- I live here
- Posts: 3190
- Joined: March 8th, 2008, 12:58 pm
- Stroker Displacement: 4563cc
- Vehicle Year: 1992
- Vehicle Make: Jeep
- Vehicle Model: Cherokee
- Location: Cyprus
- Contact:
Re: running rich.
That's normal behavior for a narrow band O2 sensor A:F ratio gauge at hot idle.rainman wrote:yes its is going closed loop, the oxy voltage is bouncing high then low consistently, it is hunting around its value of 14.2, its working its just not hunting around 14.7afr.
When the ECU goes into closed loop how does your gauge read under hard acceleration, steady cruise, and deceleration?
-
- I think I'll order a "tab"
- Posts: 44
- Joined: March 30th, 2011, 5:00 am
- Stroker Displacement: 4.6
- Vehicle Year: 1995
- Vehicle Make: Jeep
- Vehicle Model: XJ
Re: running rich.
so dropped the fuel pressure from 49 psi @wot to 43psi. @ reset the PCM.
behaves the same, injectors are open for a little bit longer. at idle that is it. still looking for 14.2-3 14.3 at idle.
14.1-14.2 at gentle acceleration, goes lean during deceleration and was only 12.3 at WOT. previously much richer 11.8. ( all afr numbers from wide band )
obviously its still learning. we will see, new narrow band oxy sensor should be here next week.
behaves the same, injectors are open for a little bit longer. at idle that is it. still looking for 14.2-3 14.3 at idle.
14.1-14.2 at gentle acceleration, goes lean during deceleration and was only 12.3 at WOT. previously much richer 11.8. ( all afr numbers from wide band )
obviously its still learning. we will see, new narrow band oxy sensor should be here next week.
Obd1 scanner.
'95 sport,4.6 stroker, 4.5" lift, 32"s, 4:10's, 8.25&SYE, taurus fan
Sydney Australia
'95 sport,4.6 stroker, 4.5" lift, 32"s, 4:10's, 8.25&SYE, taurus fan
Sydney Australia
Who is online
Users browsing this forum: No registered users and 11 guests