2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

ok i have a problem it's not the 3800 hesatation!!

Old 02-09-02 | 06:36 PM
  #1  
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From: St. Charles
Red face ok i have a problem it's not the 3800 hesatation!!

ok>>>> i don't really know if my car is hesatation or not . What it is doing is when i floor it when it reaches 3700-3800 rpm's it like "bogs" down but i can MAKE IT GO AWAY if i just give the car 1/4 of gas??? what could it be???

I need everyone's input please

And i allready did a search too but that was useless!!!!!!
Old 02-09-02 | 09:13 PM
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HAILERS
 
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From: FORT WORTH, TEXAS,USA
Its the 3800rpm hesitation. All the classic signs of it. You use partial pedal to get thru and beyond the 3800 range. It does not hesitate if you gradually go thru the 3800 range because the demand is not great enough for the secondaries to come on line. YOu can run eighty miles an hour at 4000 rpm and the secondaries won't be active if the demand is not there. Stomp the pedal and the demand is there. The secondaries do not come on line JUST because you reach 3800rpm. They will come on line at 3800rpm if your foot is biased towards the floorboard enough. The bogging at 3800 is happening because all the requirements for the secondaries to open at 3800 are there. If you ease your way thru that rpm, then the requirements for the secondaries to open are not there so you are not bogging down.
Old 02-09-02 | 09:23 PM
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From: St. Charles
AND ALL THAT MEANT??????any solutions to my problem i have listed many thing i have done in my previous thread just look for it and help me out!!!!!!!!!!!!

Im about getting ready to sell this piece!!!!!!!!!!!!
Old 02-09-02 | 11:48 PM
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It very well could be the 3800 hesitation, or ............
I had the same problem with my 86, it was not the hesitation, I have that now. It was the fuel injector resistor. Here is how I tracked it down. I pulled the connectors off of both secondary injectors, I checked for power on either pin (there are two) with the ignition on, car not running. There should be consistent power to one pin (side) of the injector. The other side will only get power in pulses from the ecu when the car is running. Power comes from the ecu to one pin and from the F.I. resistor to the other pin. I found that on my car one of the secondary's had power but the other one didn't. So then I ran a "hot" wire straight from the battery to the big multi pin connector at the resistor, I proved that the wires were good all the way through the harness up to the injectors, so the problem was most likely in the resistor. I bought a used resistor for $12.00 installed it and viola, no more bog. Now I have a slight hesitation at 3800, the infamous hesitation. I will attack that next.
The difference was with the bad resistor it was a major "bog" almost like cutting out, and the 3800 rpm problem is just a slight hesitation.
By the way the resistor is located on the engine compartment wall by the air cleaner, just in front of the shock tower. Check it out, that might be your problem.
hope this helps,
hanman
Old 02-10-02 | 06:38 AM
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All that meaningless rambling meant that the secondaries are not working properly. Don't remember your other post. Hanman sounds reasonable. As a cheap but time consuming check, you might swap the primaries with the secondaries and look for a difference in the performance prior to 3800. If its the same I'd assume the injectors are ok and that its ECU related as in good connections including the grounds . Should be less than .1ohm for the grounds to have any real confidence in them. Just for fun, in the past I've taken the secondary injector plugs off and gone for a drive. Bog is a good word for what happens. One one car I have that the previous owner had a fire on, the repaired harness to the secondary injector plugs was corrupt. The splices he put in were corroded causing erratic operation of the secondaries. I'm all for ohming out the wiring from the solenoid resistor to the small plug on the ECU. While you have a reading on the meter, massage the harness around the injector plugs and look for opens or a radical change in readings. If this problem has existed from the day you bought your car, you might look and see if the injectors are 460's. Someone might have slipped some 550's in there or put some in that are high impedence instead of low impedence. And if you think my disjointed answers are screwy, look at the non existent answers on my last question on this site. At least you get a reply.
Old 02-10-02 | 10:02 AM
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Or if your not inclined to pull the intake off, you could go to the ECU, the small plug, and put a meter on either the light green and red wire or the light green and white wire. Those are the secondary injector outputs. Should read 12v, give or take what the altenator is putting out. Should stay very close to 12v unless you drive the car and slam the throttle down, say around 2500 in third. Should show 12v until you hit 3800rpm, and at that time you should see a large voltage drop down to 7-8v. If you see that happening, I think you can safely say the ECU has not gone **** up and is pulsing a ground to the injectors.
Old 02-10-02 | 08:04 PM
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From: San Diego CA.
Problem?

My friends car had the same problem. We took off the injector harnesses and noticed one of the wires were pulled out. We pushed wire back in and whalla! Fixed.
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