This appeal was taken by plaintiff from a judgment based on a verdict in favor of defendants in an action for damages for personal injuries. There is no substantial conflict as to any material fact, and no claim is made that the verdict is not supported by the evidence. It is contended, however, that the court erred in failing to give a requested instruction on, res ipsa loquitur. We are of the opinion that the doctrine was not applicable to the facts of this case, and that the judgment should be affirmed.
Plaintiff drove his automobile to the garage of defendant Houston for a carburetor adjustment, and defendant Krussel, a mechanic employed by Houston, was assigned to do the work. The car was left standing where it had been parked by plaintiff while the mechanic took out the carburetor, cleaned and replaced it. Upon being informed by the mechanic that the job was finished, plaintiff got into the car and started the motor but it did not function properly. Plaintiff set the hand brake, left the motor running with the gear lever in neutral and released the hood by means of a “button” in the driver’s compartment to permit the mechanic to recheck the carburetor. Plaintiff then got out and walked to the front of the car to watch the mechanic who was leaning over the *169right front fender working on the carburetor. According to plaintiff the mechanic “made some adjustment and he accelerated the motor a few times and made a few more adjustments and then he raced the motor up higher, with forcefulness, and then he ran it for two or three times . . . and . . . left the motor running pretty severely and all of a sudden” the car lurched forward. It struck plaintiff and broke his leg.
Immediately after the accident, the ear was examined, and the gear lever was found to be in neutral and the hand brake set. Plaintiff testified that the car had never before leaped forward or backward when the gear shift was set in neutral.
The automobile was equipped with a “hydra-matie” transmission which makes it possible to engage the gears without the use of a clutch pedal. An assistant service manager of an agency servicing this type of automobile, called by plaintiff as an expert witness, testified that he knew of instances where a car with this kind of transmission had moved forward when the gear lever was in neutral while the motor was being accelerated. He stated that the vibration of the motor sometimes creates a strain on the gear and throttle mechanism, causing the throttle to stick and the gear to shift from “neutral” to “drive,” and that this occurs in about one car in a thousand, but that no one could foresee that it would happen. The witness stated, however, that he did not believe a car would move forward under such circumstances if the brakes were properly set. Neither of defendants had ever seen or heard of an automobile jumping forward under such circumstances, and they were not aware of the mechanical defect which plaintiff’s expert testified existed in some cars of this type.
Assuming that defendants were in control of the car while the carburetor was being rechecked, the applicability of the doctrine of res ipsa loquitur depends on whether it can be said, in the light of common experience, that the accident was more likely than not the result of their negligence. (See Escola v. Coca Cola Bottling Co., 24 Cal.2d 453, 457-458 [150 P.2d 436]; Honea v. City Dairy, Inc., 22 Cal.2d 614, 616-617 [140 P.2d 369].) “Where no such balance of probabilities in favor of negligence can be found, res ipsa loquitur does not apply.” (Prosser on Torts [1941] p. 297.)
The evidence presented on behalf of plaintiff established that at the time of the accident the gear shift was in neutral, the brakes were set, and the mechanic was accelerating and decelerating the motor while testing the carburetor. The mechanic did not go to the driver’s compartment but leaned *170over the right front fender to make the adjustment. Plaintiff watched him while he accelerated and decelerated the motor, and there is no evidence that the mechanic did or' could have done anything else which would have affected the shifting mechanism of the car. It was at least equally probable that the accident was caused by some fault in the mechanism of the car for which defendants were not liable as that it resulted from any negligent act or omission of the mechanic. Accordingly, it cannot be said that it is more likely than not that the accident was caused by the negligence of defendants, and hence the case was not a proper one for the application of the doctrine of res ipsa loquitur.
In view of this conclusion, it is unnecessary for us to consider whether the explanation of the cause of the accident given by plaintiff’s expert would have dispelled the inference of negligence under res ipsa loquitur, had the doctrine been applicable. (See Leet v. Union Pac. R. R. Co., 25 Cal.2d 605, 619-622 [155 P.2d 42, 158 A.L.R. 1008]; Meyer v. Tobin, 214 Cal. 135 [4 P.2d 542]; Connor v. Atchison etc. Ry. Co., 189 Cal. 1, 5 [207 P. 378, 22 A.L.R. 1462]; Gorden v. Goldberg, 3 Cal.App.2d 659-661 [40 P.2d 276]; Prosser on Torts [1941] p. 306; 13 Cal.L.Rev. [1925] 424.)
The court gave instructions on unavoidable accident and assumption of risk, which correctly stated the law in the abstract. It is contended, however, that they had no application to the facts of this case, and that it was therefore error to give them. (See Wallis v. Southern Pac. Co., 184 Cal. 662, 672 [195 P. 408, 15 A.L.R. 117]; Erwin v. Morris, 10 Cal. App.2d 168, 171 [51 P.2d 149].) The instruction on unavoidable accident was properly given since the jury could have found that this automobile was defective in the respect described by the expert witness. We need not determine whether it was error to give the instruction on assumption of risk, since, in our opinion, it is clear from the record in this case that the giving of such instruction could not have resulted in a miscarriage of justice.
The judgment is affirmed.
Shenk, J., Traynor, J., Schauer, J., and Spence, J., concurred.