joebugknee

Hi everyone I know this sounds like a silly question but where would I find the map sensor on my 87 vette I would of thought it would of been on the firewall but i cant seem to locate it

Keystring

http://members.shaw.ca/corvette86/Co...0View%2086.pdf

The MAF sensor is at 'K'.

Near the radiator.

joebugknee

MAP not MAF im getting a code 34

Keystring

Code 34 is a problem with Mass Air Flow sensor or MAF.

87 doesn't have a MAP system..

joebugknee

I guess that is why i cant find it then thanks ill have to look into the maf to see if i can figure out the problem

CRUZN C4

The 84s and the 90-93 have MAPs and the 85-89s have MAFs.

joebugknee

I'm pretty much at my wits end with this car I've never had such an unpredictable working engine.So many new parts and still no luck with it....

Bronze85

Elaborate on your problem and perhaps we could help.

joebugknee

i dont know where to start with it actually. first off it starts like its loading up then if it idles for about 2 minutes its just like you flick a switch and it clears right up.Then when i back out of the garage and shift to drive it stalls several times.then once it decides to drive away it seams like its loosing spark or fuel on a couple cylinders.if you go alone easy its fairly manageable but when i get passed by a four cylinder beretta and cant catch it i get fed up i have replaced all filters,plugs, wires,coil,tps,egr,checked vacuum hoses numerous times,checked all grounds,changed alternator,starter,checked fuel preasure and many other things and i cant get it figured out.any help would be great...

RetiredSFC 97

Woe there hold the wagon.

One step at a time. Describe exactly what it does at start up and then take it from there.

joebugknee

ok when i start it it idles very poor just like a carburated engine that has the choke stuck on and it likes to have alittle excellerator peddle to get going but then after about 2 minutes it just flicks right into a good smooth idle.....

Bronze85

To me it sounds like an idle air control motor issue, have you checked into that?

RetiredSFC 97

It sounds like you're not getting enough air and when you press the go pedal, it opens up the TB and allows more air in.

Take it out and clean it, using a good carb cleaner, and see if it helps. If it does I would replace it but that's up to you.

Mine was doing that and in the early stages if I held the pedal it would eventually straighten out. But this fix is temporary and it will eventually go out. Clean the TB while you're at it.

This is a "very" common problem.

joebugknee

i have also replaced that motor and made sure the measurements were correct to the tip.and while it was off gave the tb a good cleaning........Anymore ideas??

Keystring

Have you checked your injectors?

A bad one could cause the symptoms you describe as well.

joebugknee

no i have never checked them.I'm not really sure how to

Keystring

Try this link.

There is an explanation on how to test the injectors.

http://forums.corvetteforum.com/c4-t...ctors-bad.html

About 6 posts down.

RetiredSFC 97

Hey joe, how did your fuel test come out?

Also here's most all you need to know about injectors. There's a video on how to ohm them in this as well

http://forums.corvetteforum.com/c4-t...questions.html

impact1968

Sounds like when the loop status changes it idles fine.

joebugknee

i agree with the loop status idea but what changes that besides the 02 sensor witch i have also changed?