akmusclecar

I have a 88 Firebird TBI WC-T5. So I have been having a problem. When i give it gas (WOT) the car starts to spudder like it is missing on a cylinder. I have re-placed the wires, plugs, cap, rotor, coil all with MSD parts. Even at idle if i try to rev the engine, it wants to stumble at WOT around 2750 - 3250 RPM's. Any ideas or tips will be greatly appreciated. - RUSS

akmusclecar

So i still have my problem. I changed my wires out for a new set ( thinking i may have screwed them up crimping them ). That seemed to help at idle. I was able to rev the engine up to 4500rpm's at WOT ( wide open throttle ). So i went on a test drive, and what do you know? problem still exists. Here is some info on my car. 88 Firebird SE , TBI, WC-T5 114,000miles.

Things i have done to my car: Edelbrock 3704, MSD ignition system & 8.5 wires less distributor and control box, K&N filter in the stock housing, NGK V-Power Plugs, New EGR valve, IAT sensor, TPS sensor, CTS sensor, Re-built TB, New radiator,

akmusclecar

:bump: Anyone? 20+ people look, and 1 only reply?

Montage

they the right plugs?

akmusclecar

yes they are the right plugs. NGK UR4 Stock #6630 gapped to .035 "

NINÅ

When it’s missing take a look at the tach.

Does the RPM smoothly drop or is the tach erratic.

(It helps to use a racing tach with a fast response time because the stock tach might be damped).

Anyway if the tach is erratic when the miss occurs I would suspect the MSD.

akmusclecar

To give some more info. the car starts missing if i press more than a 1/4 ". In neutral revving the engine on brings the rpm's to around 3300-3500. could this be my ign. module going out? I don't want to spend the 250+ on a MSD dist. Any thought to my situation is greatly appreciated.

87transGTA

you think you might have a problem with fuel delivery?

akmusclecar

I know the fuel System is good. I have replaced EGR valve, IAT, CTS, TPS, Re-built the TB, new fuel filter, I run a K&N in the stock housing to a cone filter by the carbon canister. I have checked that the spray patter is in a nice cone shape. I just bought a new Ign. module hopefuly that is my problem.

jamon8

iTrader: (3)

sounds like you need to buy the helms manual and learn a bit of diagnosis

akmusclecar

Well that would also be a good idea. But seeing that all of this car was stock when i bought it, i figured it could use the new parts anyway. I also live in Anchorage, Alaska where i have to meet the same standards of California Emissions. Anyhow I have just replaced my "factory" ign. module to no avail. I will post a video of what is going on so everyone can see my problem.

akmusclecar

Here is a vid of my problem. This is at wide open throttle.
http://s495.photobucket.com/albums/r...Carproblem.flv


Edit: So i checked to see if i had any codes stored. I pulled up 23,24,33, and finally 42.
23- manifold air temperature sensor
24- Vehicle Speed Sensor ( speedo flutters when the dash is hot )
33- map- baro sensor
42 est ( thought it may have been timing so i know why this is showing )

Off to the parts store.i will keep this updated

akmusclecar

So I replaced my map sensor and still have the problem.... Maybe even worse. I can't figure this out. I am going to replace the manifold temperature sensor here in the next hour. Hopefully that helps!? If anyone has any suggestions they would be appreciated. - RUSS

Edit: I also made sure i am at TDC and all my wires were in the right order.

akmusclecar

Ok. so it was snowing last night, and i didn't get my manifold air temperature sensor on. I need some help trying to diagnose this. Hopefully someone will see what is happening in the video i posted and chime in.

Slick89RS

iTrader: (1)

Check the fuel pressure and make sure it's steady. If it drops badly, replace the fuel pump.

Test intake manifold vacuum at idle and let me know what it's at

akmusclecar

Unfortunately I do not have acess to a vac/ boost gauge or fuel pressure gauge.

akmusclecar

23- manifold air temperature sensor
So... I replaced this also. Still no help. I am getting pretty frustrated now. grrrr. I am honestly at a loss to what the cars' issue is.

Slick89RS

iTrader: (1)

Your wasting your time just throwing parts at it. What you need is some test equipment so we can possibly help you.

Don't you have a parts store that will loan out tools like auto zone.

Or you could take your car to reputable shop.

akmusclecar

Seeing that i am going to keep this car as long as it is running. I don't consider any repair "wasting time or money". I have a 21 year old car, If it ain't broke now it will be soon. As for parts stores, they are no help around here. And to the reputable shop.... I have been doing my own car repairs since i was 13 driving my first car a 83 jeep cherokee. I doubt your labor costs are $80-90/HR for a cheap shop. I don't trust anyone doing work on my cars either. But anyways. - Russ

Slick89RS

iTrader: (1)

I see this all the time... Consider this if you just threw $200 worth of parts at your car and haven't made any progress you could have had a reputable shop diagnose it in 2 hours @ $90hr that would be 180 plus tax. Then go to the parts store buy the part you need and install it yourself.

I've been working at a shop for 11 yrs and am one of the owners now. But I grew up here too and was in the shop as a child.

Just out of curiosity I did a gross sales chart for the last 11 yrs.... Yea sold $8.8m in repair work

Here's what it boils down to either get some test equipment so you know what direction to go or stop whining that no one can help you.

akmusclecar

Ok so i got a boost/vacumm and air/fuel gauge this morning. I am at work so I won't be able to hook anything up until i get off. And to " slick" I only have spent around $150 for my sensors, Holley fuel pump# 12-903 and my gauges. Oh wait.... you are an owner of a repair shop, I see why you would think that I would have to spend $200 just for a manifold temp sensor and map/ baro sensor ( mark-up costs ). You sir are the reason i don't have any shops working on my car. Some of us don't have the money to spend for (you) a shop to work.... oh wait diagnose our cars. I will spend $200 of my hard earned money on parts i might or might not need, before i go and let a shop have my car for a undetermined amount of time. I do understand as a shop owner you would like to keep as much $ in your line of work as possible. I have no hard feelings about it. I just cannot justify bringing my car to a shop to have them tell me it could be a simple problem. Then i would look like an . - Russ

akmusclecar

Update: I istalled a air/fuel gauge to see if the car was leaning out or running rich. At idle the gauge stays around the normal mark, but when i give it gas she leans out pretty bad. It looks like i am going to install the Holley 255lph pump i picked up this weekend. How long should it take to drop the tank if i cut the exhaust? And is there any common problems i will probally have getting the tank out? any help is appreciated . -Russ

Damon

Man, that thing just won't reve for nothin' when you open the throttle. You're probably either running out of fuel or your cat is badly plugged up.

fychelio

did u ever figure it out? my cars doing similair stuff

akmusclecar

Yes I finally got it figured out. Damn fuel pump. I started to unbolt the rear-end components... Then as i struggled to get the tank out of the way I see the hole where the last owner cut the "access hole". Well unfortunately i had to clean up the hack job the last owner left. I finished pulling the pump to find the strainer was fully clogged. Installed the new pump, put all back together and now my bird has all the power i want, when i want it.

87transGTA

well thats good and i did mention is fuel delivery good well atleast you got it fixed

speedlimit96

yeah your timing might be off, did you make sure it was at TDC before you put back in the distributor and mark the distributor and plugs? you might have the wrong firing order or the distributor is too far advanced or retarded, i know it sounds dumb but i know if have forgotten to do it before!! also did you mess with any gaskets or anything?