# acting like its got a rev limiter



## TRAVIS75 (Oct 30, 2009)

Been awhile since I posted.

Brief description: Had a tune up done on it 6 months ago, plugs, wires, cap, rotor, fuel filter. I did those things partly because I got it at our auction and had no idea when it was last done. But mostly because it ran like crap and got about 12 mpg. After basic tuneup I got all the way up to about 13.5mpg.

Its never idled right, and the only code I get is for the EGR.

The problem I've got now, is when I 1st start it up, it really doesn't like to idle, even worse than it was before. And as I rev it up, it revs up really rough like, if I take off down the road like this, it hits a certain RPM (doesn't have a tach so I couldn't tell you for sure the exact RPM) and then thats it, almost acts like it floats the valves, won't accelarate any more, unless I shift into 2nd (this occurs at around 15 mph). It continues to do this until it has reached full op temp. At which time, it will then idle fine (ironic since theres never been a day since I got it that it would ever stay idling high enough to barely keep it running).

This vehicle has also always had what I call the "hiccup", where I can be cruising at 35 at it will just all of the sudden buck a couple times, and resume normal driving. Go about 2 miles and repeat the same thing, it does it any RPM and any speed when under load.

Hope this isn't an overload of info, but I know I hate it when someone posts with no kind of info, speaking of which, this is an 87 pickup, 4x4 with the 2.4 M/T.

Any ideas?


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## SPEEDO (Jun 9, 2003)

is it throwing any codes?


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## TRAVIS75 (Oct 30, 2009)

If I remember right it was code 32, the code for the EGR. 

I've talked to a couple of mechanics who said "Yeah its possible, but generally those aren't the symptoms of a plugged or bad EGR"

I've priced them new and here locally, they are about $120.00. If I knew for sure it would fix the problem, I wouldn't have a problem with doing it, but I don't want to start randomly replacing the "yeah its possible" parts trying to fix it.

I've had this pick up for 3 years now, and want to give it to my son who has asbergers, I want his 1st vehicle to be dependable, not only for his sake, but for my peace of mind.

If I've got a picture of what exactly to replace, I can do it, I have a helluva time with the chiltons manuals pictures.


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## saudade (Apr 10, 2010)

Does it do this in neutral or can it rev past the cutoff?

Check the Mass Air Flow sensor on the side of the throttle body.


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## TRAVIS75 (Oct 30, 2009)

It used to be that it only hiccuped under load, had no limits as far as RPM range, and it always idled really low, exhaust smelled clean (for being exhaust), and that was underload and acclerating having someone right behind me with their window rolled down.

Now when I first start it up, in neutral, when revving it up, I think it is getting to much fuel, because the exhaust smells really gassy, or like unburnt fuel, it does this really bad when its cold, and after it warms up it continues to, in my opinion run rich, but in neutral it revs more smoothly, but will as I was saying before, act like it can only go to a certain RPM, if I give it more gas, RPMs will go higher, but accelaration doesn't seem to be there unless I up shift.

I will attempt to locate the MAF on the throttle body. I haven't completely eliminated that it isn't the temp control, I had to replace that winter when the vehicle wouldn't hardly start when it was very cold outside, after I replaced it with a new one, it would start.

So as an un-scientific test, I unplugged it one day before going to lunch to see if it ran any differently, and it REALLY ran like crap, so my logic is that it is working correctly.


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## GeoBMX4Life (Mar 25, 2010)

I'm with saudade...the MAF sensor. I'm willing to bet...and its easy to find, pull the air filter and housing, be careful of the O2 sensor on the left of the housing, once thats removed, the MAF is on the lower left of the TB...3 screws I think.


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## TRAVIS75 (Oct 30, 2009)

Couple of questions regarding the MAF

First is, can it be bypassed for testing purposes, or is there a way to test it.

What is the interchange as far as other vehicles that would have the same one on it. When I look up throttle bodies on my computer at work (I work at a wrecking yard) it is saying that the throttle body for example on an 87 Nissan P.U. is exclusive to 87 only, and so on and so forth for 88 and 89, however the engines interchange, this doesn't seem likely to me, but we don't have any of those vehicles here for me to even rob the part off as a test.

I understand that all I am needing to replace at first is the MAF, however our system will only let me look up the throttle body as a complete unit, thus giving me no interchange for just the air flow meter.

And lastly, when I've tried looking just that specific part up online, thru Oreilly's and Napa both, I'm not coming up with any availability on that part, so if anyone has any links to where I can get a new or rebuilt one from I would appreciate that also, in the mean time I will continue to look for a used one as soon as I hopefully get a more defined application.


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## GeoBMX4Life (Mar 25, 2010)

*MAF*

PM zanegrey on this site, he has just the airflow meters for sale. And yeah, its very difficult to find...I had to buy the whole Throttle body to replace mine last year. I beleive that 87-95 are the interchange years. Car-Part.com--Used Auto Parts Market is where I eventually sourced mine from.

As far as testing it...its easiest to just remove it and check to see if the two wires are still connected.


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## TRAVIS75 (Oct 30, 2009)

yeah, I get alot of calls from car-part.com looking for parts from our yard, I will keep looking though thanks


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## GeoBMX4Life (Mar 25, 2010)

TRAVIS75 said:


> yeah, I get alot of calls from car-part.com looking for parts from our yard, I will keep looking though thanks


 Again...send zanegrey a private message, he sells them at a reasonable price too!


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## rjdifiore (Oct 1, 2013)

*Mine does the same thing*

I've replaced everything, maf, throttle body, and nothing worked!!


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## saudade (Apr 10, 2010)

rjdifiore said:


> I've replaced everything, maf, throttle body, and nothing worked!!


You should start a new thread. Don't forget specs for your truck.


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## rjdifiore (Oct 1, 2013)

saudade said:


> You should start a new thread. Don't forget specs for your truck.


It's a stock pos 4wd 88 truck


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## SPEEDO (Jun 9, 2003)

have you pulled codes?? it should save you time and $$$


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