My car is boosted for over 6 months now and I never had a problem like this before. Whenever I step on the gas...my car would simply just die. The other night I had to force driving it home...as im driving...the rpm would fly up and down and the check engine light would flash like crazy...bogging like a bitch. Has anybody ever had this problem before?

I thought it was a dizzy problem, borrowed a good working dizzy. Switched it and still the same problem. I think it has to do with the map sensor....what do you guys think? What are the symtoms of a bad map sensor when boosted?

 

i believe a bad or faulty map sensor would throw the car into "Safe mode".

safe mode only allows the car to rev up to about 3.5 - 4k rpm's and it runs real shitty.

but your symptoms dont sound like that...

 

Sometimes when my car is just sitting there...idling. The RPM would bounce rapidly up and down 1k-2k...only the rpm on the tach would bounce but the motor sounds like its still idling @ 800.

 

Sounds like a vacuum leak to me.

I had a IAC bolt fall out and caused the idle to surge like crazy. I'd just check over all the places where you can have a vacuum leak.

Check what code is being thrown, that'll help diagnose the problem.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Marauder &raquo;</TD></TR><TR><TD CLASS="quote">Sounds like a vacuum leak to me.

I had a IAC bolt fall out and caused the idle to surge like crazy. I'd just check over all the places where you can have a vacuum leak.

Check what code is being thrown, that'll help diagnose the problem.</TD></TR></TABLE>
hmm....

 

Check your code, it should be stored. But the symtoms seriously sound like a faulty dist.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Luserkid &raquo;</TD></TR><TR><TD CLASS="quote">Check your code, it should be stored. But the symtoms seriously sound like a faulty dist. </TD></TR></TABLE>
As of right now, I dont have actcess to my car. Im away in LA, but I will check it out when I get back home though. Any other ideas?

 

flashing check engine light means catalyst damaging, that is super bad. i wouldnt even start the car before checking codes and running some test

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by postman &raquo;</TD></TR><TR><TD CLASS="quote">flashing check engine light means catalyst damaging, that is super bad. i wouldnt even start the car before checking codes and running some test</TD></TR></TABLE>
what? lol

 

ttt

 

Im wondering what causes the rpm tach to bounce without my motor "bouncing" with it. The needle on the rpm tach would bounce 1k-2k sometimes....but the motor isnt really bouncing/reving with the tach. Simply....the tach bounces by itself.

 

The tach is driven off the distributor signal. It's possible that the gauge cluster is bad, but that wouldn't have any effect on the way the car functions. Check the code and then see if you can borrow a buddy's ECU. It's possible that your car's brain is fried to ****.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Archidictus &raquo;</TD></TR><TR><TD CLASS="quote">The tach is driven off the distributor signal. It's possible that the gauge cluster is bad, but that wouldn't have any effect on the way the car functions. Check the code and then see if you can borrow a buddy's ECU. It's possible that your car's brain is fried to ****.</TD></TR></TABLE>
thanks for the comment, anybody else?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by trooper0641 &raquo;</TD></TR><TR><TD CLASS="quote">Im wondering what causes the rpm tach to bounce without my motor "bouncing" with it. The needle on the rpm tach would bounce 1k-2k sometimes....but the motor isnt really bouncing/reving with the tach. Simply....the tach bounces by itself. </TD></TR></TABLE>

That tends to be the ignitor in the distributor.

 

Does anybody know about a bad map sensor with boost? Would that be the problem?

 

maybe your coil is going bad. but i would get my hands on some diagnostic tools to see if it wuz throwin codes. bye bye

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Marauder &raquo;</TD></TR><TR><TD CLASS="quote">

That tends to be the ignitor in the distributor.</TD></TR></TABLE>

thats what i was thinking cause it happened to me before, but he said he swapped out dizzys...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CRXified &raquo;</TD></TR><TR><TD CLASS="quote">

thats what i was thinking cause it happened to me before, but he said he swapped out dizzys...</TD></TR></TABLE>
Im going to hang myself.

 

yeah flashing check engine light means catalyst damaging such as caris misfiring or crank sensor is bad to lean to rich, things that are bad enough to cause emissions to be of catalyst damaging bad nad thats why it flashes. obd1 or 2

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by postman &raquo;</TD></TR><TR><TD CLASS="quote">yeah flashing check engine light means catalyst damaging such as caris misfiring or crank sensor is bad to lean to rich, things that are bad enough to cause emissions to be of catalyst damaging bad nad thats why it flashes. obd1 or 2 </TD></TR></TABLE>

a flashing CEL means catastrophic engine failure, since in this guys case i'm pretty sure he dosn't have a cat but if he does sure he could have started to come apart, but who carses, its just gonna blow out the back of the car. it won't suck back in.

now why is it flashing? what injectors? what basemap? pull your plugs and check them, and check spark, what code are you getting? what miss code are you gettting? sounds like a miss to me. and yes also check your map sensor check voltage values and such, and also check a known good one. just out of curiosity also pull the IAC off the back of the intake and see if carbon is built up in there, just for the hell of it. anything else let me know

 

all the things i have read about this thread... vacume would not make ur RMP jump up and down like crazy... honestly i think u have a bad ground wire somewhere along ur wireing harness or maybe something wrong wit the ECU... from what u have posted i honestly believe its an electrical problem....

 

well actually i take that back about the vacume... it would make it jump up and down but honestly i think it has to do wit electrical...

 

Boosted, way to get up your post count by making a new post and not editing your first one.

OP: When the RPM display goes all over the place and the motor is running smooth, that is usually going to be your dist. A flashing CEL is usually a sign that you ecu is done. If you can, try switching out ECU's when you get back to your car. Best of luck.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sicky &raquo;</TD></TR><TR><TD CLASS="quote">Boosted, way to get up your post count by making a new post and not editing your first one.

OP: When the RPM display goes all over the place and the motor is running smooth, that is usually going to be your dist. A flashing CEL is usually a sign that you ecu is done. If you can, try switching out ECU's when you get back to your car. Best of luck.</TD></TR></TABLE>

in 6 years i've been a tech i have never seen a Flashing MIL normally leading to a bad ECM........

normally to bad injectors, or ignition.

dude give us some more info, what setup are you running, wiring? everything let us know

 

sorry guys when i say flashing....i meant ON AND OFF and not constantly flashing. and today i just found out the problem. the problem waaassss....the ******* thermostat ground was KIND OF loose....not hand loose but wrench loose. so i tighten the ground and added another ground to it just incase that was the problem. thanks for all of your help.