driveability questions

I have a 88 chevy corsica I changed Fuel injecters, fuel filter, E.G R. valve runs little better but when gets warmed up starts to run sluggesh . Before i put all the stuff on it hesitated and had black smoke now. runs smoth and no smoke have any Suggestions Please need help need car for wife for school .
Thank you.

Any trouble codes? Temp sensor could do some of those things, as could map, of maf sensor (if so equipped.) Check out my article under "learn about your car's many systems" under the "computers" section.
George

Make: Ford Model: Ranger supercab Year: 1986 Engine Size: v-6 Repairs: it has a vibration in the dash and it is not a vaccum leak and it is not the computer. What might this problem be??? Thanks Jesse Wade

Could be a lot of things. Most likely a rough idle is causing the vibration: or is it a "on the road" vibration? spark plug wires, clogged carb or fuel injector, etc. could cause this.
A "on the road vibration" could be from u-joint or suspension problems, even shocks and tires!
Would really need to see the truck to run some tests on it.

George

My problem is the while driving the car, it's like a horse pulling a wagon and the wagon starts going faster than the horse, so the horse jumps and pulls the wagon. (the car bucks) I have replaced the carb, EGR valve, fuel pump I had a tune-up. Sometold me its the transmission. Can you help figure this out?

I could figure it out if I could see the vehicle!
A couple of thoughts: If it was the tranny, it would be the lockup torque converter going in and out. This can be disconnected/unplugged ( it is controlled by the computer) and if the problem goes away, that's it.
Could also be a fuel supply problem: (fuel filter, pump, tank strainer)
If you're in the Gainesville area, come on by and I can tell you a lot better.

George

I have a 89 ford taures that when the motor gets hot it stalls someone said that there a switch somewhere that might be bad. I would appricate some in put from you

THANK YOU

Actually there are several sensors and switches which can cause stalling at idle. I'd really need to hook the car up to my computer scan tool to find out the problem.

$35 for the diagnosis, plus whatever parts are needed, and the labor to put them on.

George

Am a single mom who has taken the car to 3 different shade tree mechanics...they all say "there's something between the computer and the battery" I had one who told me that all the links were good. still cant figure out whats wrong, and they have taken me for over a thousand dollars just to tell me they dont know! I need this car to support my kids please help. The car won't do anything. There is no response when you turn the key. Sent the computer itself off and was told there is nothing wrong with it. Any info. you have would be greatly appreciated.

First, the computer has nothing to do with the engine "turning over". If nothing at all happens when you turn the key, either the ignition switch, neutral saftey relay or switch, the starter itself, or the wires in between are bad.

Check out iATN.net for a decent mechanic near you. I'm a member, along with 20,000 techs worldwide. I'm sure some of mechanics involved in IATN are better than others, but at least they're computer literate and know where to go to get answers to tough questions.

George

To whom it may cocern,
Please don't delete or skip over this e-mail. I have recently purchased a 1988 NISSAN king cab 4x4 pick-up truck that is idling very harsh, after you start the truck and it reaches operating temperature the idle waivers between 650-2000 rpm. I have had the points, plugs and wires, oil and filter, and air cleaner replaced. I have also had the carbureator rebuilt and the engine re-timed but the idle is still waivering and now when you accelerate the engine starts bogging out. Please if you can possibly give your thoughts on how to fix my problem or what all parts might be involved in repairing my engine I would appreciate it very much.

Firstly, your car doesn't have points, so if someone says it does, I'd listen to someone else.
Could be throttle position sensor maladjusted/defective. Could also be the decel system, which admits air into the intake on closed throttle deceleration.

George

I have a question about a Pontiac Bonniville. 3.8 engine(3800) 1988. The Vin number is C. My question is one day the car start up fine and the next day it doesn't start at all. The timing chain was just change about 2 weeks ago. I noticed that when it is very cold that's when I seem to have the most problems. I tried turning the car on it doesn't start but it does crank followed by a lot backfire that seems to be coming from the engine. I have heard many things but I really confused on what to do. I have heard that it the timing belt again, or the CTS Coolant Temperature Sensor. ALso it could be the distributor coil. Any suggest would be helpful. Thanks

Could be temp sensor: could also be mass airflow sensor or any number of other things. Tap on the MAF sensor (easy, now!) If engine misfires, that's a problem. See if the scanner reading off the computer seems reasonable for the temp sensor. It can be within specs and still be wrong.

Any trouble codes read?

Where are you located?

George

I live in Lowell Massachuetts. I'm a novice when it comes to fixing cars. I do have a maual. When is the temperature sensor located. What about the MAF. Should I replace the distributor coil or is that a waste of time. I also have trouble finding the trouble codes. I'm aware of when the jumper wire should be place however no codes flash when I try it.

Temp sensor is by the in thermostat housing. (2wireconnector: the 1wire sensorruns the gage or light) MAF sensor is the thing with wires in it part of hose connecting air cleaner to engine. Try jumping the other set of terminals: should blinkout the codes. Check out iATN.com... we're 20,000 techs worldwide: can find a good tech in Mass. A lot of stuff you've just got to have a scan tool for. Often a labscope too.

MAYBE YOU CAN HELP. 1987 CHEVY S-10 PU W/ 2.5 4 CYL MOTOR ENGINE CODE 25 INDICATING BAD ATI SENSOR (HIGH TEMP. INDICATION) ACCORDING TO HAYNES AUTO MANUAL WHAT IS AN ATI SENSOR? NO ONE AROUND HERE SEEMS TO KNOW. SYMTOMS ARE ;WHEN ACELERATING BAD HESITATION; POOR FUEL ECONOMY ;MANIFOLD WHERE O2 SENSOR GETS REAL HOT QUICKLY APPRECIATE YOUR INPUT THANKS!!!!!

By my book code 25 is a bad MAT sensor: manifold air temperature sensor. It's a thermistor in the intake manifold. I think you have a timing/lean run problem too: esp. if manifold glows. Code sets if man. temp exceeds 275 deg. f.

George

Hi, I was wondering if you could help me. I have a 1990 Dodge Dakota 4x4. For the last few months I have been having trouble with it. I will be driving and all of a sudden I lose power. I have lights, radio and all that, but no engine. When this first started happening I could just press the gas and it would restart. Now I have to pull over put it in park and turn the key. But sometimes it takes about 10 minutes for it to start. When I turn the key it sounds like it wants to start but it doesn't catch. I just had a tune up when it first started and it did run better for a while. But now its getting bad again. It doesn't matter if the engine is cold or hot or damp. I have been putting fuel injector cleaner in the gas, but it doesn't seem to be doing much help. I was wondering if you had any suggestions on what could be causing this. If you do, please let me know. If you have a price range also that would help. Thank you for your time and help.

Intermittant problems are always hard to fix: but I'd look at the fuel supply: relay, fuel pump, etc. Could also be spark/module/computer prob.

Self checks: when you turn engine on, just to where the dash idiot lights turn on, not to where the starter engages and turns the motor over, the elect. fuel pump will run for 10 sec then shut off. A whirring sound comes from the tank...........listen for it!

When it stops, leaving you on the roadside.. see if you can hear the sound... no sound: bad fuel pump or relay.

A bunch of other stuff could do the exact same symptoms: any electronic component can go intermittant, and shakey spark can mimic shakey fuel supply.

Another DIY test: careful: (no pacemaker folks!!!!) Pulloff a plug wire, insert a key off your keyring: hold 1/4 inch from metal part of engine, have friend turn engine over. No spark/ weak spark... module or coil problem.

90 percent sure fix: shotgun method (where you replace all the likely suspects)........replace fuel pump& relay& filter, ignition module, & coil.

Fun stuff, eh?

George

I have a 1993 nissan pickup 4x2, 2.4 liter with 70,000 miles on it. It has an intermittent starting problem that occurs randomly. i've replaced the fuel pump, fuel filter, spark plugs/wires, and cap/rotor. Any ideas what might be wrong? thanks, john.

The electronic ignition module in distributor gave a lot of trouble: unfortunately it will do fine and test fine until it messes up. Occasionally it will set a code, but not always. When it does this, check for spark. No spark makes this more likely.

Or bring it by: I can see if there are any codes.

George

I have a '91 Chevy Caprice (305. auto/overdrive, throttle-body fuel injection). I have a problem with spark knock. The timing is right on the mark & I use 93 oct., gas. Oh, & I just changed plugs. Is it true, that chevy 350's & 305's, from '88 to '90 or '91, had problems with distributers (bad bushings or something)? It only does it, when cruising at a certain speed & under load, like when cruise control is set. Not when excellerating! PLEASE respond ASAP,

Should be all computerized spark advance. Check EGR system operation. Mfr's at one point said a "little" spark knock is OK. Did not say what "little" was. Newer systems have a knock sensor: yours may. This "listens" for the knock and the computer retards the spark briefly.

George

I loved your web site! It armed me with information to hit my mechanic with. I just spent $670.97 on my 88 Z24 convertible, and it still runs like crap. In fact, after having 3 ignition coils, new plugs and wires, a module (whatever that is) and an o2 sensor, my car still clunks and dies after driving on the highway and then coming to a stop. It always starts but usually dies 2 or 3 times when I put it in gear. So far if I let it idle for 2 or 3 minutes then it does ok if I stay under 40 mph. I live in Iowa so I can't come to see you. Now the mechanic says I need a map sensor and a TPS. Did I get boned? Should I take it back or find someone else. I really love my car and drive 100 miles a day. I would appreciate any help .

>TPS and MAP could certainly do this. Prices seem a bit high, but don't know how pricing is in your area.

> Check out iATN.net: I'm a member, and they are a good network. Some member shops are better than others, I'm sure, but at least they're all on the net and know where to get help with those "tough ones!"

George

>Make: GEO >Model: Tracker >Year: 96 >Engine Size: ? >Repairs: Noise upon start up and when pulling up hills, when engine cold. My repair shop did a road test and detected the noise. >Suggested it ought to be under warranty (36,372 mi.). He thought it was a problem with the lifter. I called my dealer's service >department...they said the warranty was up at 36,000 mi. Do you have any idea what this problem might be and what the cost would >be to fix...do you know if Trackers are known for this type of problem? Great web site. Thanks, Marianne

>Try checking ign. timing: could be preignition/spark knock. (see my website: ign.timing under "learn about your car's many systems)

George

Hello, I have a car related question that I could use some car advice on: I bought a 1987 Chevy Celebrity 2.5 FI (4 Cylinder) this winter. The car is in great shape and only has 25,000 original miles. The car was well-maintained but it was sitting for the past three years with very little use. The only repairs it needed when I bought it was an exhaust pipe and a serpentine belt. After a bit of background here is my question: When I have my car in park while it idles the "Service Engine Light" comes on. However, when I take off the light goes off after 5-60 seconds. Also, one time I started the car and the "Service Engine" light came on during my entire drive to school. The car was running real rough and the performance was lacking to say the least. However, after I parked the car and came back to it 2 hours later the car was running fine. The car has new plugs and wires (the mechanic who fixed the exhaust indicated the plugs were like new so that may not be the problem.) This winter I averaged 18-20 miles a gallon so I can't really diagnose the problem. Do you have any advice or suggestions? Any Comments would be appreciated.

>The computer which controls the engine relys on several sensors to control fuel air mix and ignition. If one of their sensors reads out of specs, the computer ignores it and substitutes a "middle of the road" value for its calculations. While it receives bogus values, it will light the "check engine" light. When the readings go back within specs, the light turns off, but the "trouble codes" are kept. (see my article www.econofix.com/computers.html) You can get the codes out with a scan tool, or by grounding the diagnostic connector and counting the light flashes: 12 will blink 3 times, followed by the actual codes. Each code flashes 3 times. Look up the code meaning in any good service book: Haynes, Chilton, Motor, etc. They should have test stuff for each code also.

George

I won't ask you for step by step instructions, just pick your brain for some troubleshooting ideas. I have a 1990 Nissan 4x4 regular cab truck that I bought used about 3 weeks ago. It ran fine until last Monday morning. I got into my truck and warmed it up for a few minutes before heading for work. I only got about 200 yards when the truck started to lurch violently (like either the ignition or the fuel was cutting in and out). I have since determined that the truck starts and idles fine. I can also race the engine with no missing. But, when I hold the throttle steady at about 2500 rpm it goes into this rhythmic up and down rpm mode all by itself. It only does this when the engine is warm. This model has a self-diagnostic mode on the ECU and it indicated that the throttle postion sensor circuit was faulty (4 red LED flashes and 3 green) but when I tested it with an ohm meter while my wife stepped on the gas slowly (engine not running) it seemed to change resistance as expected. I have since changed the air cleaner, ignition rotor and fuel filter (they all needed it anyway) but the problem still exists. The temperature sensor also changes resistance as expected when the engine warms up. I should mention that the day before, I washed the underside of the truck to get rid of dirt (maybe got something wet?) and that night I used it to jump start my 1982 Toyota pick up. Any suggestions? First, check the power supply to the TPS for proper input voltage: if this circuit is shorted/bad/loose connector all stuff could screw up. The opto-electronic distributor gave a lot of trouble on Nissans: that could be the problem. Ohm out the TPS wires to computer connector. The TPS would generally give a hesitation/stall on sudden acceleration, not as severe as you describe: don't think it's the TPS. Hope this is of some help!

George

I have a 1988 fuel injected sentra and I get about 18mpg. I am dissatisfied with that milage. Do I have a problem ? Also my car hard starts once it has rested for about 2hrs, it works fine after that. I get about 160 km/hr when I open it out n the highway.Could you advise me what to do to rectify the problem.

At 160 km/hr 18 mpg might not be bad, but anything under 100 km/hr (about 68 mph) a Sentra should get 25-30 mpg, even more! Check your plugs: If they are black (should be dirty white/light tan) you are running rich. This could be from a lot of things: temperature sensor is one of several possibilities. Does a "check engine/service engine soon" yellow light come on? Could even be a dirty air filter!

George

>Make: Mitsubishi >Model: Galant >Year: 1995 >Repairs: When i press the gas,my car stuters. If I needed to press the gas in an emergency,It wouldn't take off like It should.If i leave a red light or entering a high way,I have trouble,It doesn't feel like the transmittion. HELP!

>If it behaves normally on light acceleration, it may be the throttle position sensor. See my stuff at www.econofix.com.computer.html for a better description.

George

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Thank you for visiting the ECONOMECHANIX WEB SITE. Please feel free to comment. We also serve the surrounding communities of Alachua, High Springs, Hawthorne, and Newberry! Gainesville has been my home since 1974, and I've loved Gvl and the Gators since I came here in the fall of 1974 to attend the University of Florida. I loved it so much I stayed and opened my car repair business. Originally it was out of the back of a 1963 Chevrolet wagon, but in 1977 a fellow mechanic and I opened an auto repair shop with actual walls, etc. I stayed in the same location for 26 years, and recently moved my operation to property I bought 15 miles east of Gainesville. I am doing most all the repairs myself now, having reduced my overhead from $1500 per month to practically nothing. I do work by appointment only. I mostly work only on my established customers cars, but I will occasionally take on new clients. E-mail me and I will either make arrangements to look at your car, or I will recommend you to someone who will.

George G. Scott, Jr.

Driveability Questions