hard starting when hot, maf sensor

Hello everyone. My '88 C4 starts great when cold but when she's hot I have to pump the accellerator pedal to start it. I originally thought that I had a leaky injector or two but I believe it's the mass air flow
sensor or burn off relay(s). The engine was hot and I removed the maf sensor and sprayed throttle body cleaner through the sensor (thinking maybe it was dirty) and the car started without any problem afterwards. That only lasted so long and now she's doing the same thing. How can I test the maf sensor before I spend the cash on a new one? Also, how can i test the burn off relays as well? Thanks in advance.
walt '88 conv
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
i forgot to mention that i pulled the codes from the car and a 32 code popped up. The service engine soon indicater light came on a few days ago on the thruway but hasn't been on since. I installed a new battery yesterday (battery was old and dying) so i cleared the codes when i changed it. 32 is an EGR code i believe, any thoughts?
walt '88 conv
wallster wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

would be leaning towards the mas sensor myself..
I got away from that computer all together. got tired of my 84 c-4 always throwing codes. all I have to do now is watch the gages, like the good old days :-)
my2
--
"Key"
=====
---snip---
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
this looks weird (that i keep replying to my own question) but the more i dig into the problem, my thinking changes. I found a service bulletin from '91 regarding the MAF relay (or relays with the bosch MAF set up that this car has) that the relay can take a dump and still test okay as well as not produce an SES code. The relays are $11. so i'll change them first. They might not be resetting the mass flow sensor thus producing a false fuel signal/reading. As far as the 32 code (EGR), the car idles fine and runs strong so i doubt the valve or switch is faulting. I've driven the car over 200 miles since that SES was shown (at thruway speeds) and the SES hasn't come on. This could have been a false code (or the beginning of something to come... D'OH!) I'll post later if the relays fix the problem for future google searches.
walt '88 conv
wallster wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Here's a good article explaining how and what a mass air flow sensor does. It also explains what the relays do. OEM relay stock number is 14089936 (for those who are looking for parts numbers) http://corvettebuyers.com/c4vettes/maf.htm
walt '88 conv
wallster wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I changed both MAF relays (burn-off and power relay) as well as the air filter and she fires right up. I drove it about 25 miles and between this morning and yesterday it hasn't started hard once, just turn the key. Autozone stocks the relays (part# MR44 @$10.99ea.) Hope this helps anyone else with the same problem.
walt '88 conv
wallster wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I have an '85 with a similar problem, hard starting when warm. Starts great in the morning but will give me trouble even after it sits 8 hours at work. I've looked everywhere I can think of and no one lists these sensors for an '85. Does anyone know if it takes the same ones as the '88? Thanks in advance. Brad

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.