Need some help...car running terrible

1988WHTGT

Member
Mar 31, 2005
270
0
17
Guyton, GA
Ok, so my car developed a miss a couple weeks ago. Since then I've done the following: TFI Module, cap, rotor, wires, plugs, coil. Still runs terrible. Idles rough and accelerates rougher. Although on the test drive I gave it to it and it took it for a second and then went back to running crappy. It smells like raw gas and theres smoke coming out of the exhaust on idle and accelerating. The smoke looks blue but u can smell the gas. I also looked under it while it was idling and the smoke was coming from the passengers side muffler ( I have dumps) Anybody have any ideas? Any help is appreciated. Thanks
 
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As suggested, dump the codes.

Dump the codes and see what the computer says is wrong… Codes can be present without setting the Check Engine Light.

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Walmart.

Or for a nicer scanner see http://www.midwayautosupply.com/detailedproductdescription.asp?3829 – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $35.

WalMart may have the above LCD display scanner for less than $35.
 
Do a compression test. If you have any leakage, this this the best way to find it. Do not tear an engine down just because you think it might have a problem.

Only use a compression tester with a screw in adapter for the spark plug hole. The other type leaks too much to get an accurate reading.Your local auto parts store may have a compression tester to rent. If you do mechanic work on your own car on a regular basis, it would be a good tool to add to your collection.

With the engine warmed up, remove all spark plugs and prop the throttle wide open, crank the engine until it the gage reading stops increasing. On a cold engine, it will be hard to tell what's good & what's not. Some of the recent posts have numbers ranging from 140-170 psi. If the compression is low, squirt some oil in the cylinder and do it again – if it comes up, the rings are worn. There should be no more than 10% difference between cylinders. Use a blow down leak test (puts compressed air inside cylinders) on cylinders that have more than 10% difference.
 
I wouldn't think a head gasket would make the computer just dump gas into the motor but I'm an idiot so I don't know. Pull the codes, see what it says, and compression test it like said above before you touch anything else.
 
I'm curious how the diagnosis was made.

JRichker's advice about a compression test for starters is wise.

Also, as part of the code retrieval, run the cylinder balance test. You noted an engine-miss and this test will help narrow down the source of the miss (helps you to be really anal when testing and diagnosing a particular cylinder and any adjacent to it).

Good luck.
 
UPDATE: Left the car in the carport for almost 2 days with the battery unhooked. Hooked it back up today so I could move it to clean the carport out some and it started up and ran nice. So I drove it around the block. No stuttering or smoking. So I took it down the road after it got to normal temp, got on it and it ran better than it has in a long time. I'm confused now. Did the computer just need to be reset or something? Maybe it was having a brainfart and needed to be reset?
 
1988WHTGT said:
UPDATE: Left the car in the carport for almost 2 days with the battery unhooked. Hooked it back up today so I could move it to clean the carport out some and it started up and ran nice. So I drove it around the block. No stuttering or smoking. So I took it down the road after it got to normal temp, got on it and it ran better than it has in a long time. I'm confused now. Did the computer just need to be reset or something? Maybe it was having a brainfart and needed to be reset?
You'll know soon enough after it has some time to adapt.

Glad to hear it's runnin better for now atleast. That tells you it can if it wants to. The rest is just fine tuning.

Good luck.
 
Well, it did the same EXACT thing again today. The part that sucked this time was that I was a lot farther away from home than last time....its been running perfect since my update from previously. Anyone think its the computer? I have it all unhooked again and I'm going to leave it to see if it will work again when I hook it up. If it does it would have to be the computer wouldn't it? This car has been converted to MAF using an A9L computer, but that was a year and a half ago.
 
Before you spend $$$ for parts, spend 2 cents for a paper clip & dump the codes. That will tell you what sensor or system is failing.
 
Ok, pulled codes and this is what I got:
31
81
82
84
85
95

Does this help with anything? This was all done Key On Engine Off and the car was cold because I'm afraid to let it run with it running the way it is. Any help with this is greatly appreciated. Thanks. Oh yea, my car doesn't have EGR or any emissions crap on it.
 
1988WHTGT said:
Ok, pulled codes and this is what I got:
31
81
82
84
85
95

Does this help with anything? This was all done Key On Engine Off and the car was cold because I'm afraid to let it run with it running the way it is. Any help with this is greatly appreciated. Thanks. Oh yea, my car doesn't have EGR or any emissions crap on it.

hmm, lets see...
31 - egr valve position sensor
81, 82 - air pump solenoid
84 - egr valve solenoid
85 - canister purge solenoid
95 - fuel pump secondary circuit

if they were all koeo codes, then theres not much to go on. 81 as a continuous code, has to do with the map sensor, but idk if you have speed density or mass air.