More on the "hesitation epic".... Danno???
03-22-2003, 06:01 PM
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Three Wheelin'
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More on the "hesitation epic".... Danno???
I just installed an Autometer boost gauge and air/fuel gauge. So now,back to trying to nail down the hesitation, I pressure tested the intake again. I pressurized it with a couple PSI while the crankcase line was still connected, I noticed some air leaking around where it plugs into the block. I then plugged this line at the J Boot and put 10psi to it. I noticed a good bit of air coming from the ventury tube and its hoses. I was able to pull apart the venturi, I epoxied it back together, replaced one clamp and tightened the other. No more leaks there !!! I notices a very small leak from the 'swivel' on the ReliaBoost, The CV was leaking, so now its bypassed. The only other leak was a very slight leak in the body and connector of the idle compensator. So, I put everything back together and I still have the hesitation when in 'closed loop' Not improved at all, despite fixing all but a couple of small leaks.With the meter, I can see it sweeping back and forth in closed loop.
Now heres what I have noticed....If I accel hard, it goes instantly to the 2nd or 3rd green LED rich and no hesitation...If I accel about 1/2 to 3/4 throttle, just as I start to build boost, it will hesitate...stumble. I look at the gauge and its still in closed loop, the instant it drops out of closed loop, the hesitation stops.
If I put the coding plug in the DME for ROW maps, The gauge shows mid to high yellow on cruise and if I accel, goes to the same point on the rich side (2nd or 3rd green) and has no hesitation.
Heres my thought...the DME isnt dropping out of closed loop early enough. Is there anything that could cause this?
I also left the crankcase hose vent to atmosphere and plugged the J-boot as a test...no difference in point or amount of hesitation or AFM readings.
Now heres what I have noticed....If I accel hard, it goes instantly to the 2nd or 3rd green LED rich and no hesitation...If I accel about 1/2 to 3/4 throttle, just as I start to build boost, it will hesitate...stumble. I look at the gauge and its still in closed loop, the instant it drops out of closed loop, the hesitation stops.
If I put the coding plug in the DME for ROW maps, The gauge shows mid to high yellow on cruise and if I accel, goes to the same point on the rich side (2nd or 3rd green) and has no hesitation.
Heres my thought...the DME isnt dropping out of closed loop early enough. Is there anything that could cause this?
I also left the crankcase hose vent to atmosphere and plugged the J-boot as a test...no difference in point or amount of hesitation or AFM readings.
03-22-2003, 09:46 PM
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I think I'm still having the same thing happen... I noticed it happening under medium throttle at around 1.0-1.3 bar boost on the factory gauge. If I lay into the throttle (with new GURU chips!) it is less noticable or doesn't occur.
We've shared our story before so I know you've replaced pretty much everything under the hood trying to fix it. Fixing the leaks will pay off in any case, but good luck getting this resolved.
Ron
We've shared our story before so I know you've replaced pretty much everything under the hood trying to fix it. Fixing the leaks will pay off in any case, but good luck getting this resolved.
Ron
03-22-2003, 11:01 PM
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Yep...Its a pain,and I'm running out of things to replace. I am thinking out of the box here...the car runs great on Euro fuel maps and can switch between maps in 'real time' I'm thinking of connecting a vacuum switch to the 1.8k resistor I have connected to the DME computer. This would be open when on vacuum, which would use the USA maps and 'closed loop' when cruising, but when vacuum drops to a preset value, say 5 inches, then it would close and select the ROW maps. It could be the best of both worlds and would basicly throw the car into open loop earlier.
03-23-2003, 02:28 AM
#4
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"If I accel about 1/2 to 3/4 throttle, just as I start to build boost, it will hesitate...stumble. I look at the gauge and its still in closed loop, the instant it drops out of closed loop, the hesitation stops."
What does your air-fuel gauge show when it stumbles? I assume it's too rich since lean mixtures only cause laziness (stumbles only when super-lean like no fuel at all).
"If I put the coding plug in the DME for ROW maps, The gauge shows mid to high yellow on cruise and if I accel, goes to the same point on the rich side (2nd or 3rd green) and has no hesitation."
Ok, so this confirms that the stumbling you get is due to too rich a mixture since the ROW maps are about 5-10% leaner across the board. This small amount won't really show up on the LED air-fuel gauges.
"It could be the best of both worlds and would basicly throw the car into open loop earlier."
Hmm, the toggle between closed-loop O2-feedback operation and open-loop/WOT operation is triggered only by air-flow and TPS velocity. The maps that are currently in use won't change that switch-over point. The distinction here is the difference between the program-code vs. data. The program that's running is always the same; it's hard-coded into the CPU and the open-loop toggle is part of the algorithm. The fuel-maps are data that's on the chip and they only affect the amount of fuel that's metered.
"I am thinking out of the box here...the car runs great on Euro fuel maps and can switch between maps in 'real time' I'm thinking of connecting a vacuum switch to the 1.8k resistor I have connected to the DME computer. This would be open when on vacuum, which would use the USA maps and 'closed loop' when cruising, but when vacuum drops to a preset value, say 5 inches, then it would close and select the ROW maps. It could be the best of both worlds and would basicly throw the car into open loop earlier."
Why don't you just leave it in the ROW maps all the time? The WOT/full-load/open-loop maps are identical for all three maps; it doesn't matter which one you select when under open-loop operation.
My guess here is that you still have a vacuum leak some place. This leaks out air that has already been measured by your AFM. Then when the DME injects matching fuel, there's too much due to the missing air. The richer USA maps makes this over-fueling even worse as indicated by the stumbling. Just stick to the ROW maps full time and you'll be OK.
What does your air-fuel gauge show when it stumbles? I assume it's too rich since lean mixtures only cause laziness (stumbles only when super-lean like no fuel at all).
"If I put the coding plug in the DME for ROW maps, The gauge shows mid to high yellow on cruise and if I accel, goes to the same point on the rich side (2nd or 3rd green) and has no hesitation."
Ok, so this confirms that the stumbling you get is due to too rich a mixture since the ROW maps are about 5-10% leaner across the board. This small amount won't really show up on the LED air-fuel gauges.
"It could be the best of both worlds and would basicly throw the car into open loop earlier."
Hmm, the toggle between closed-loop O2-feedback operation and open-loop/WOT operation is triggered only by air-flow and TPS velocity. The maps that are currently in use won't change that switch-over point. The distinction here is the difference between the program-code vs. data. The program that's running is always the same; it's hard-coded into the CPU and the open-loop toggle is part of the algorithm. The fuel-maps are data that's on the chip and they only affect the amount of fuel that's metered.
"I am thinking out of the box here...the car runs great on Euro fuel maps and can switch between maps in 'real time' I'm thinking of connecting a vacuum switch to the 1.8k resistor I have connected to the DME computer. This would be open when on vacuum, which would use the USA maps and 'closed loop' when cruising, but when vacuum drops to a preset value, say 5 inches, then it would close and select the ROW maps. It could be the best of both worlds and would basicly throw the car into open loop earlier."
Why don't you just leave it in the ROW maps all the time? The WOT/full-load/open-loop maps are identical for all three maps; it doesn't matter which one you select when under open-loop operation.
My guess here is that you still have a vacuum leak some place. This leaks out air that has already been measured by your AFM. Then when the DME injects matching fuel, there's too much due to the missing air. The richer USA maps makes this over-fueling even worse as indicated by the stumbling. Just stick to the ROW maps full time and you'll be OK.
03-23-2003, 07:27 AM
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Three Wheelin'
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Thanks Danno,
I will probably do as you say..run ROW maps, I will be pulling the intake sometime and replacing all the hoses. And I can keep testing.
It doesnt stumble when going into open loop and rich...Its still in closed loop while its stumbling. Just as soon as the AFM shows its out of closed loop and rich...then it quits stumbling.
If its a vac leak, then you would think that with each leak I find is repaired, it would get a bit better, which it doesnt.
When I started this, I had a lot of leaks. all repaired except a small one around the body of the idle compensator.
BTW...Have you ever torn down the idle compensator to see if has replaceable o rings?
I will probably do as you say..run ROW maps, I will be pulling the intake sometime and replacing all the hoses. And I can keep testing.
It doesnt stumble when going into open loop and rich...Its still in closed loop while its stumbling. Just as soon as the AFM shows its out of closed loop and rich...then it quits stumbling.
If its a vac leak, then you would think that with each leak I find is repaired, it would get a bit better, which it doesnt.
When I started this, I had a lot of leaks. all repaired except a small one around the body of the idle compensator.
BTW...Have you ever torn down the idle compensator to see if has replaceable o rings?
03-23-2003, 12:41 PM
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Danno
I dynoed my stocker last weekend and I was real lean on the bottom end according to the snifffer. It was not a real dyno, more of a rolling smog machine w/ a HP load capability, not a Mustang or a Dynojet - hey it was a PCA meet and it was free.
Anyway, brand spanking new stock injectors and it was fine up high at WOT. It is real sluggish on start-up driving. FQS is set to 1st pos. and I did not use the electrical jumper.
Any suggestions for me? The sluggishness improves after warm-up, but getting out of my driveway in the AM I have to rev up to 2500 just to get going! (?)
I dynoed my stocker last weekend and I was real lean on the bottom end according to the snifffer. It was not a real dyno, more of a rolling smog machine w/ a HP load capability, not a Mustang or a Dynojet - hey it was a PCA meet and it was free.
Anyway, brand spanking new stock injectors and it was fine up high at WOT. It is real sluggish on start-up driving. FQS is set to 1st pos. and I did not use the electrical jumper.
Any suggestions for me? The sluggishness improves after warm-up, but getting out of my driveway in the AM I have to rev up to 2500 just to get going! (?)
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03-23-2003, 01:02 PM
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If you disconnect the alltitude compensator...the round device mounted right above the KLR computer and connect a 1.8k ohm resistor to the DME connector(brown and brn/blue wires), this will select the ROW maps.
You are suppose to also disconnect and jump to ground, the O2 input, However, I have tested both ways and there is no difference. I have it on good autority that the O2 sensor can remain connected, its just ignored. Try it...you'll like it <img border="0" title="" alt="[Wink]" src="wink.gif" />
You are suppose to also disconnect and jump to ground, the O2 input, However, I have tested both ways and there is no difference. I have it on good autority that the O2 sensor can remain connected, its just ignored. Try it...you'll like it <img border="0" title="" alt="[Wink]" src="wink.gif" />
03-23-2003, 02:00 PM
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</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by awilson40:
<strong>I have it on good autority that the O2 sensor can remain connected, its just ignored. Try it...you'll like it <img border="0" title="" alt="[Wink]" src="wink.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">Thanks. I assume the O2 sensor signal would still be available for use with a gauge?
Do you happen to have any pictures of how/where you spliced, etc? It would be interested to wire this as a switched set-up that you could easily toggle back and forth.
Ron
<strong>I have it on good autority that the O2 sensor can remain connected, its just ignored. Try it...you'll like it <img border="0" title="" alt="[Wink]" src="wink.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">Thanks. I assume the O2 sensor signal would still be available for use with a gauge?
Do you happen to have any pictures of how/where you spliced, etc? It would be interested to wire this as a switched set-up that you could easily toggle back and forth.
Ron
03-23-2003, 02:25 PM
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Sorry, no digital camera... And yes, by doing it this way, the O2 gauge still works. If you look in the passenger foot well, you will see the altitude compensator mounted right to the floor board, it has 1 connector with the brown and brown/blue wires. If you live below 5000 ft(I think), this is not used, disconnect it and the 1.8 k Ohm resistor plugs in there. My Radio Shack didnt have a 1.8 k so I had to build one...In series resistance adds, so I soldered several resistors together and to 'butt' connectors the right size to plug into the connector where the altitude box was plugged into.
You could also wire a toggle switch in series with the resistor to switch. Open selects USA maps with O2 sensor adjustment (closed loop) Closed with 1.8k resistor would select ROW maps with no O2 adjustment. Its real obvious on the meter...With USA maps, its dithering back and forth at idle and cruise, on ROW maps, it remains fairly constant. Bear in mine that the closer to 14.7 ratio you get, the more it will vary from lean to rich anyway. On ROW maps, mine holds steady at the 1st green bar (autometer gauge)at Idle, Cruise control on at 55 shows last yellow to next to last yellow, let off the gas even a bit and it will drop to lean. WFO will show 2nd or 3rd green.
You could also wire a toggle switch in series with the resistor to switch. Open selects USA maps with O2 sensor adjustment (closed loop) Closed with 1.8k resistor would select ROW maps with no O2 adjustment. Its real obvious on the meter...With USA maps, its dithering back and forth at idle and cruise, on ROW maps, it remains fairly constant. Bear in mine that the closer to 14.7 ratio you get, the more it will vary from lean to rich anyway. On ROW maps, mine holds steady at the 1st green bar (autometer gauge)at Idle, Cruise control on at 55 shows last yellow to next to last yellow, let off the gas even a bit and it will drop to lean. WFO will show 2nd or 3rd green.
03-24-2003, 12:11 PM
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Well,
I have an adjustable vacuum switch coming, I'm dying to test this out just to see what happens.I will use the vaccum switch to let the car stay in closed loop USA maps for cruising and idle, then switch fuel maps when vac drops to near zero. This will be interesting.
I have an adjustable vacuum switch coming, I'm dying to test this out just to see what happens.I will use the vaccum switch to let the car stay in closed loop USA maps for cruising and idle, then switch fuel maps when vac drops to near zero. This will be interesting.
03-24-2003, 01:36 PM
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Ron,
I just looked up the schematics on the 86 and 87.They also show the altitude switch connected to the same place and the 1.8k resistor to switch to ROW maps.
I just looked up the schematics on the 86 and 87.They also show the altitude switch connected to the same place and the 1.8k resistor to switch to ROW maps.
03-24-2003, 05:00 PM
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</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by coolhand:
<strong>where can you get an ohm resistor?</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">Radio Shack?
<strong>where can you get an ohm resistor?</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">Radio Shack?