Where is MAP sensor on 88 Cutlass Ciera?

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Hi all,
I have a 1988 Cutlass Ciera, 3.8 ltr, Automatic Tranny.
My check engine light comes on and when I check the trouble codes it flashes 34, which my chiltons manual says is a bad MAP Sensor. Unfortunatley neither myself or my friendly neighborhood NAPA guy can find a MAP sensor listed for this year of Cutlass Cieras in his books, or when we have done a visual inspection.
Any one have advice or ideas

Thanks

posted by  Gpurv

Code 34 DOES NOT and NEVER HAS said that you have a bad MAP/MAF sensor. Code 34 indicates a malfunction within the MAP system or an unexpected and incorrect reading. While your NAPA guy might be friendly, he's not a mechanic or apparently a real good parts guy. The engine in your vehicle does not have a MAP but rather MAF. Somewhere you're missing details... Very important details. Check for a vacuum leak before you replace the part.

posted by  vwhobo

well i just check a couple of manuals here it is for buick caddy's chevy's olds and pontiac depending on you car and engine combo look at the attachment not to bad for an inexperianced mechanic

posted by  osborste

What is your point moron... Except to partially confirm what I already told him?

posted by  vwhobo

what is your problem

posted by  osborste

Read the wording of your last post and see if you can figure it out. We all know who the comment was aimed at and you're not so special as to not be called on it.

posted by  vwhobo

are you here to help people or just give them a hard time with questions and rude answers

posted by  osborste

Read post #2 of this thread and well over a thousand more for your answer. If you don't like it then I'm quite sure you can leave. Nobody is forcing you to post here, are they?

posted by  vwhobo

well enjoy "YOUR" site

posted by  osborste

It's not my site, it's everyones site. Just keep in mind that the people who have kept it alive for years won't and shouldn't be expected to change to suit you. Remember, you joined us, not the other way around.

posted by  vwhobo

Honestly man, your second post was just complete trash. Are you like, just trying to get a better ranking or something?

Usually when you can't find a listing for a part on a vehicle that is over 10 years old, it means that there simply isn't one. GM code 34 has generally meant a malfunctioning Mass Airflow system.

Usually the computer will sense a voltage drop in the sensor with will set off a code. The voltage drop across the sensor could be brought about by a million different problems or other malfunctioning systems within your vehicle. It would be wise to get your MAF sensor tested by your local parts shop (it isn't hard to do) and when it tests good (because 99% of the time they are) you can begin looking for the real problem.

(my guess is you got this code by grouding the output connector and catching glimpses of flashing check engine lights. most advance auto parts' stores have the correct diagnostic for it and they work a whole lot better. i work there unfortunately)

good luck though.

posted by  carls47807

Just take a look at the crap under "valve cover problem ".There is 4 pages of opinions attached to it .He is even convinced that I do not know how to spell properly,that I am 12 years old ,and that my 7000 hours plus flying hours were obtained from a crackerjacks box. One flight would be all it would take after I pin the VSI TO -12000.

posted by  the lobster

Most auto zones, advances, etc. will not check codes on a car not equipped with OBDII systems.

posted by  tbaxleyjr

In my Haynes manual, (issue 19025), section 6-16, it plainly states (and I quote) under code 34: " This code will set when the signal voltage from the Manifold Absolute Pressure (MAP) sensor circuit signal is too high. The engine must idle for up to 5 minutes to set this code. The ECM will substitute a fixed MAP value and use the TPS to control fuel delivery. Replace the MAP sensor".
As I replaced the TPS and also the MAF sensor previously, (upon the suggestion of a certified gm mechanic and it still did not fix the problem) I figured, (Based on the book), that the MAP sensor was the problem.
But as I have since found out, and you so derogatorily state there is no MAP sensor.
So I am back to square one.
I might add although any assistance you can offer would be greatly appreciated, your attitude can stay away. I joined this forum to not only fix my car problem but to possibly help others. I have read some of your other responses and to be honest I would be surprised if you have any friends...
Best Regards
gpurv

posted by  Gpurv

The previous message was meant for "wwhobo", my apologies to the other folks who I imagine are just trying to find or offer assistance in a genial fashion
Best Regards,
gpurv

posted by  Gpurv

If you could get over your pathetic little hurt feelings for just a second and actually read that post I've already told you what to look for, a VACUUM LEAK. Also pay close attention to the EGR valve. A leaking or stuck open EGR will set a 34 because it too is a vacum leak.

Alternately you could go piss up a rope. I'm sure you have PLENTY of friends, unfortunately they all eat shit and bark at the moon.

posted by  vwhobo

As I stated in my original message, I have gone through the vacuum system.
I checked the EGR previously and it seems to be in order.
I think I would ask you not to reply to my threads in the future.
your lack of maturity reflected in your verbal assaults, and name calling would be funny if it was meant in jest, but unfortunately I, and everyone else who reads your "advice" know what type of person you are. It must be nice to know it all as you obviously do, well except for having the ability to get your point across without being offensive.

posted by  Gpurv

Okay Ace (or is that Ass), I'll bite.

1. Show me where it stated in your beginning post where you "have gone through the vacuum system". You can't because you didn't. Strike one.

2. Show me where you said anything about checking your EGR previously in an earlier post. You can't because you didn't. Strike two.

3. Perhaps if you were as intelligent and mature as you want to appear you would have read this, http://www.car-forums.com/talk/showthread.php?t=2200 . Following those simple instructions would have given you the opportunity to provide us with a well detailed description of your problem and what you've done intead of your half assed attempt of an explanation. I am more than happy to help those who wish to help themselves. However, you are not one of those people.

4. Don't waste the bandwidth asking me not to answer, unless you are now the new owner of this forum. Remember, you joined this forum, we didn't join you. When you have provided 10% of the useful information that I have here then and only then will I even consider your request. Well, not really. Strike three, you're out.

posted by  vwhobo

I apologize for the lack of info on the vacuum check
(I had written it in another forum and forgot I hadn't put it in this one)
as far as EGR is concerned as it is somewhat a part of the vacuum system I didn't specify to that either).
I am still curious why the Haynes manual would say to replace a MAP sensor that doesn't exist but I will leave that for another day.
Either way, I am done trying to figure it out.
This car ran pretty well for the 40K miles I put on it, (it now has 178K)
and from what I have seen throughout this forum and another one is that this type of 3.8L and GM engines used in this style of car in general from 1986-1994 seem to have numerous problems that even certified GM mechanics can't figure out with their diagnostic tools.
As I have changed all of the EXISTENT sensors, and gone through the vacuum system presently and at times in the past, and it is still not wanting to run properly I guess it is time to wave bye bye to this car.

Thanks though for the verbal abuse and name calling it brought me some humor in an otherwise stressful situation.
No matter how bad I think I may be I will always know that your wife, if you even have one, & your kids have it a lot worse than I could ever dream.

posted by  Gpurv

This Bit Of Info Is From A GM Dealer.(service Manager)MY NEIGHBOR
The Maf/map Sensors Can Be Triggered By A Clogged Catalytic Converter.the Maf Sensor Needs To See More Airflow Than What It Is Getting,and Thinks There Is A Vacuum Leak.to Check This,remove The O2 Sensor And Check For Excess Pressure (over 2 Lbs Or So).
Excessive Idling And Or Misfires Will Take Out The Catalytic Converter........OH BY THE WAY,IF YOU CHECK THE POST THAT I LEFT YESTERDAY ABOUT MY 89 OLD 98 3.8L YOU WILL SEE THAT THERE IS A SIMILARITY OF SORTS.THE SERVICE MANAGER SEEMS TO THINK THAT THE 1989 HAS A MAP SENSOR.NOT MAF SENSOR.I WILL CHECK INTO THAT ONE.

posted by  the lobster

Thanks for the input, I will check it out
I seem to recall that a few months ago after I replaced the muffler and connector pipe, (between muffler & catalytic converter), that I heard a rattling sound under the car when I would start it in the morning to let it warm up.
I mentioned to my wife then that I thought some of the "pellets" in the C.C. might have come loose.
Car ran fine then but maybe a call to a bone yard for a "new" C.C. is in order
I will let you know how it turns out.

Thanks
gpurv

posted by  Gpurv

you don't say if at driving speed the car is fine then at idle it starts to stumble/die out if so use something to tap gently on the maf sensor while car is idleing smooth if maf is bad it should stumble or die out found this info on another post/site

posted by  osborste

Sorry, the car runs excellent at medium to high speeds.(30 mph and faster)
It is when I let off the gas coming to a stop, or if I put it into gear to initially take off. The rpm gauge and engine goes up and down and 99% of the time will stall if I do not put it in neutral and keep the rpms over 2K
Also if I am just in park and I push on the accelerator it revvs up, but when I let off the gas it drops in rpms suddenly and if it keeps running will lope for about 2 minutes until it settles into a consistent idle.
I noticed that the times it stalls when I do this there is a whooshing noise like the sound a carbuerator makes if it blows in reverse. (this car is fuel injected though).
Just in case I wasn't checking the EGR properly,(thanks wwhobo) I replaced it today but still the same problem.
I spoke with a GM mechanic today and he said a partially clogged catalytic converter could be the problem but others have told me that usually if a converter is clogged you will notice at high speeds and going up hills.
This car flies when it is on the highway and doesn't mind hills at all.
I think my next option might be to take the MAF sensor I put on (New) back to the parts store and ask them to check it.

posted by  Gpurv

also in the post i read the remanufactured one's the guy went though 3 before he got a good one so even rebuilt one might be bad try it

posted by  osborste

APPARENTLY,THAT CAT IS A COMMON PROBLEM.I HOPE THE INFO HELPS.

posted by  the lobster

If you don't have an adapter to fit a gage in the O2 sensor opening, a good muffler shop can help.

posted by  tbaxleyjr

Or you can simply test for a clogged cat with a vacuum guage, but... A clogged cat will manifest itself as poor performance above idle, under load, at cruising speed, under acceleration, etc.

Every description I've read in this post points to a MAF or a vacuum leak. Alternately, if you have a badly stretched/worn timing chain it will cause low vacuum at idle and this problem will surface.

If only I could see the data stream I could nail this for you in about 10 minutes. Less if I had a pilot to tell me how to do it.

posted by  vwhobo

Ureka,
It would seem that the MAF sensor, (from the parts store), I changed was defective.
So Instead of going to a parts store again and buying a reconditioned one for $70.00
I went to a bone yard and for $15.00 my car is running the way it should be.
Thank you all for your input.

posted by  Gpurv

glad to hear that

posted by  osborste

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