hi all i have a 1988 chevy van running the 5.0 305 TBI engine

i have trouble starting from cold almost like flat battery has new battery and rebuilt alternator all wiring cleaned and checked, when the engine is warm starts fine, idles low guessing between 500-800 not excatly sure, when i pull away i have to put my foot down just to get it to pull away or it backfires through the TB, sometimes causing it to cut out, other times i can back of the throttle and floor it and it will recover, the temp does not go over 100f on the gauge which im sure is way to low and the heater is not getting hot,

i am going to replace the thermostat and clean up the CTS connections have removed the EGR valve and its clear but does not hold a solid vacumn slowly leaks(not sure if that is correct though) was thinking of removing it and the aiv will take a couple of pics to show as not sure if i can also what should the timing be set at as wondering if it is out, last thing would a bad CAT cause any of this as i think it is original

many thanks all i need to sort it this weekend as is my everyday motor thanks all

 

any DTC codes at all?

 

not sure how to check the codes on my van and which no/letter the pins are
did have the service light come on yeserday for about 5mins then went off while driving this makes the 4th time in 4 years normaly stayed on for couple of secs then went off can find anyone who can read the codes, but have been told i can find out crossing 2 pins not sure which though would you have an diagram of which pins mine has a rectangle socket if is the right one

thanks

 

as far as i know for OBD1 you always connect/jumper A and B, on Camaros/Firebirds, it is the top two holes all the way to the right on the ALDL connector under the drive side dash

when you jump them with a paperclip turn your key to ON but do not start the van

the SES light will flash code 12(lets you know the diagnostic mode is working properly), which should look like this

flash.......flash flash

it will do that 3 times (each code will flash 3 times before moving to the next code)

try to find the codes and then look them up




http://www.extreme-check-engine-ligh...%20Decoder.htm

that looks to be a good site for more info on DTC codes

 

thanks will have a look at that and have a go at reading the codes

ok have been out to try and look at the codes jumpered the A/B pins the SES light did 1 fast flash then stayed on constant waited for five mins nothing else happened

does the SES light have to have been on for a while to register any codes as when it has shown up has been for a couple of secs then gone of and the last time was on for about 5 mins,

comes on when i start the van the goes out as normal would this indicate an intermittent fault on a sensor possibly ??

will try cleaning the connections and trying again

 

sorry for the late reply, it never told me you edited the post lol, but sometimes the connection with a paper clip is not the best, i actually went to Autozone, and they have a "tool" that looks like a key with two little prongs at the end, i think they keep them behind the parts counter, its called a GM code key and it goes on your key ring, ill get a picture and post it,

but as far as the codes, if the SES light comes on for even a second while driving chances are it threw a code, and that code will stay in the memory until you clear it

so do me a favor if possible and unplug the ground on the battery for 5 minutes, hook it back up and drive the van around and see if the SES comes back on, then check for codes again

 

hi and thanks for that will see my local locksmith if they can do me a key,
i think i might have found why the ses light kept coming on found a bare wire on the oil pressure switch has not come on for the last couple of days though so might be good now, readjusted timing by ear is running better but still still cuts out under idle sometimes almost as idle to low cleaned out the egr no vacumn loss on it now, but have found my TBI to be leaking fuel from the spindle where it enters the throttle body and can here air sucking in there stops when warm so got to sort that now lol

 

Sounds good, keep us posted, you wouldnt happen to own a thirdgen would ya? if not you should buy one lol