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

hesitation throughout and loss of punch

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Old Jun 14, 2010 | 06:23 PM
  #1  
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hesitation throughout and loss of punch

So i've been searching and havent really found any conclusive info that applies to my situation so please help me diagnose my problem?

So just recently out of no where i've been getting really bad hesitations while i accelerate. It makes it very hard for me to even start off in 1st.

When i accelerate it seems like i'm going on and off the accelerator but im holding it still in actuality. i have a small hesitation at 3500 which is the usual thing but it hesitates all around the rpms.

If i floor the pedal, the car accelerates but not at the normal accelerating speed and it just seems like there is a lack of power.

The car is an 86 na and all stock with just a free flowing bonez cat.

please throw out just advice and wat i should check before replacing things.

Known issues:
-slave is leaking and needs replacement.
-throw-out and pilot bearing need replacement.
-Clutch needs replacement as well.
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Old Jun 14, 2010 | 07:24 PM
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Whipping thru traffic.
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What kind of gas you using?
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Old Jun 14, 2010 | 07:39 PM
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regular 87
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Old Jun 14, 2010 | 08:25 PM
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rotors excite me
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Fuel filter? Bad TPS? Bad O2 sensor? Fouled plugs? Leaky injector(s)? Wouldn't hurt to check the compression either, just to be sure.
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Old Jun 14, 2010 | 09:05 PM
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kk fuel filter was just replaced so that shouldnt be the cause, o2 sensor is fairly new as well at most one year.. TPS i'll have to check, plugs were replaced but will have to check. injectors? maybe havent touched them.

thanks for the input speed i'll check back with updates.

anyone else have any other things i can check?
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Old Jun 14, 2010 | 09:46 PM
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did you change the plug wires recently too? might be those, I have had them arcing like crazy before for some reason (maybe just stock 1986 wires,idk it was when I first got the car) and it acted like you are saying. does it feel like its misfiring kinda? definintely look in the bay at night to see if you have arcing from the wires. could a bad coil pack cause this too guys? I don't know about the pack but just my .02
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Old Jun 14, 2010 | 10:03 PM
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lite rotary = easy push
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try the grounds the 3500 hesitation is a bad ground that screws up the secondary injectors
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Old Jun 17, 2010 | 02:53 AM
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Will try all this and check back soon. out of the country for a bit but thanks for everyone's feedback!
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Old Jun 17, 2010 | 01:21 PM
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First thing is always *check for codes*
Make any repairs as necessary to clear codes
Check for closed loop operation at cruise
Check fuel pressure
Check for proper operation of EGR
Check for proper operation of double throttle diaphram, thermovalve, delay valve
Check TPS for max/min resistance values, dropouts, and then adjust
Check AFM for resistance values and dropouts
Check for excessive backpressure (does the problem go away if you pull the O2 sensor and leave the hole open?)
When was the last time the fuel injectors were cleaned? If it has been more than 30k miles, that could be part of the problem...
Water themo sensor
Intake air temp sensor
Altitude sensor
Boost sensor

Backprobe the connectors to the ECU and compare voltages against those pubished in the AFM, for 'ignition on/not running', and 'running, at temp' conditions.
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Old Jun 17, 2010 | 02:49 PM
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if it feels like its bogging, could possibly be belt slippage, the alternator could use some readjustment, the belt could be worn... if it occurs alot when you turn (sharp, or not) its the belt mos def
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Old Jun 19, 2010 | 01:21 AM
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oooh wow great thanks everyone. not really sure on how to test everything that calpatriot said but i'll check the fsm cause i think they have all the info there. i'll check back in a month when im back in the states
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Old Nov 30, 2010 | 02:52 PM
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AZ

i am having the same problem.
i own an 88 na
i have my suspicions about the EGR valve being the problem as i can hear a loud ticking that sounds like it is coming from the top of the motor, where the EGR would be.
my hesitation is mostly in the idle-3.5k rpm range, after that she seems to run smooth however with lack of power
NOTE: this happens very infrequently which is also concerning. some days it will be perfect and some days a mess... another guess for the EGR, ground short, or injector failure.
my vehicle also has hard starts in the morning cold and stumbles all over the place till she's warm.

im not sure why but my finger is pointed at the EGR. could i be right??
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Old Nov 30, 2010 | 03:04 PM
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Originally Posted by the faster one
i am having the same problem.
i own an 88 na
i have my suspicions about the EGR valve being the problem as i can hear a loud ticking that sounds like it is coming from the top of the motor, where the EGR would be.
my hesitation is mostly in the idle-3.5k rpm range, after that she seems to run smooth however with lack of power
NOTE: this happens very infrequently which is also concerning. some days it will be perfect and some days a mess... another guess for the EGR, ground short, or injector failure.
my vehicle also has hard starts in the morning cold and stumbles all over the place till she's warm.

im not sure why but my finger is pointed at the EGR. could i be right??
The EGR is just for emissions and would not affect the drivability of the car unless it was causing a vacuum leak as far as I know. While the car is running spray some carb cleaner on it and observe for a change in the idle. No change in idle thus llikely no leak.
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Old Apr 12, 2011 | 11:32 AM
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I have a 91 N/A and having the same issue. I just bought it, the owner before me took the air pump off and 6P valve actuators off. Do I need them? He also told me it is Streetported and I need to run Premium, is that true? I am going to try the solutions previously posted on my car today.
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Old Apr 12, 2011 | 07:13 PM
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there is a known grounding issue to the secondary fuel rail that allows the secondarys to intermittently work causing a form of hesitation and irregularity

also, you would need the airpump if you wish to utilize the auxiliary ports and the VDI. it is not necessary to have these things, but it is also dependent on how your car is setup. are the port sleeves still installed in the vehicle or are the actuators and sleeves removed? no sleeves= no power until 3800... dont think premium is required after a street port but ill let someone more knowledgeable chime in on that.

Last edited by the faster one; Apr 12, 2011 at 07:20 PM. Reason: revision
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Old Apr 12, 2011 | 07:17 PM
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Check your coil packs for spark. Same thing happenned to me and it turned out to be one of the leading coils. I was running on one rotor.

Oops, just realized this is an old thread...Oh well.....Check your coil packs anyway.

Last edited by armen505; Apr 12, 2011 at 07:28 PM.
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Old Apr 12, 2011 | 07:22 PM
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^^ +1
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